WO2017010370A1 - ニトリルゴム組成物およびゴム架橋物 - Google Patents
ニトリルゴム組成物およびゴム架橋物 Download PDFInfo
- Publication number
- WO2017010370A1 WO2017010370A1 PCT/JP2016/069997 JP2016069997W WO2017010370A1 WO 2017010370 A1 WO2017010370 A1 WO 2017010370A1 JP 2016069997 W JP2016069997 W JP 2016069997W WO 2017010370 A1 WO2017010370 A1 WO 2017010370A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- nitrile rubber
- parts
- weight
- silica
- carboxyl group
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/34—Silicon-containing compounds
- C08K3/36—Silica
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F236/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds
- C08F236/02—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds
- C08F236/04—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated
- C08F236/12—Copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated with nitriles
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/0008—Organic ingredients according to more than one of the "one dot" groups of C08K5/01 - C08K5/59
- C08K5/0016—Plasticisers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/0008—Organic ingredients according to more than one of the "one dot" groups of C08K5/01 - C08K5/59
- C08K5/0025—Crosslinking or vulcanising agents; including accelerators
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/04—Oxygen-containing compounds
- C08K5/10—Esters; Ether-esters
- C08K5/11—Esters; Ether-esters of acyclic polycarboxylic acids
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/04—Oxygen-containing compounds
- C08K5/10—Esters; Ether-esters
- C08K5/12—Esters; Ether-esters of cyclic polycarboxylic acids
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/16—Nitrogen-containing compounds
- C08K5/17—Amines; Quaternary ammonium compounds
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/16—Nitrogen-containing compounds
- C08K5/17—Amines; Quaternary ammonium compounds
- C08K5/175—Amines; Quaternary ammonium compounds containing COOH-groups; Esters or salts thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/54—Silicon-containing compounds
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/54—Silicon-containing compounds
- C08K5/541—Silicon-containing compounds containing oxygen
- C08K5/5435—Silicon-containing compounds containing oxygen containing oxygen in a ring
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/54—Silicon-containing compounds
- C08K5/544—Silicon-containing compounds containing nitrogen
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L15/00—Compositions of rubber derivatives
- C08L15/005—Hydrogenated nitrile rubber
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L9/00—Compositions of homopolymers or copolymers of conjugated diene hydrocarbons
- C08L9/02—Copolymers with acrylonitrile
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K2201/00—Specific properties of additives
- C08K2201/002—Physical properties
- C08K2201/006—Additives being defined by their surface area
Definitions
- the present invention relates to a nitrile rubber composition having good normal state physical properties and capable of giving a rubber cross-linked product having a small dynamic heat generation, and a rubber cross-linked product obtained using such a nitrile rubber composition.
- Nitrile rubber (acrylonitrile-butadiene copolymer rubber) has been used as a material for automotive rubber parts such as hoses and tubes, taking advantage of its oil resistance, mechanical properties, chemical resistance, etc.
- Hydrogenated nitrile rubber (hydrogenated acrylonitrile-butadiene copolymer rubber) in which carbon-carbon double bonds in the polymer main chain of rubber are hydrogenated is further excellent in heat resistance, so it is used for rubber parts such as belts, hoses, and diaphragms.
- Hydrogenated nitrile rubber hydrogenated acrylonitrile-butadiene copolymer rubber in which carbon-carbon double bonds in the polymer main chain of rubber are hydrogenated is further excellent in heat resistance, so it is used for rubber parts such as belts, hoses, and diaphragms. Has been.
- nitrile rubber composition for example, in Patent Document 1, a nitrile copolymer rubber (A) having an iodine value of 20 to 80 and white carbon (B) having a specific surface area of 20 to 48 m 2 / g are used.
- a composition comprising it is disclosed.
- the rubber cross-linked product obtained by the composition of nitrile rubber disclosed in Patent Document 1 has good normal state physical properties, but has a large dynamic heat generation and is used for a vibrating part, for example, a vibrating part. In some cases, it is not suitable for use in sealing applications.
- the present invention has been made in view of such a situation, and a nitrile rubber composition capable of providing a rubber cross-linked product having good normal physical properties and small dynamic heat generation, and such a nitrile rubber composition.
- An object of the present invention is to provide a rubber cross-linked product obtained by using.
- the present inventors have contained ⁇ , ⁇ -ethylenically unsaturated nitrile monomer units in a proportion of 5 to 60% by weight and an iodine value of 120 or less.
- the above object can be achieved by a nitrile rubber composition obtained by blending a carboxyl group-containing highly saturated nitrile rubber with a silica having a specific surface area of 70 m 2 / g or less and a polyamine-based crosslinking agent, and completed the present invention. I came to let you.
- a carboxyl group-containing highly saturated nitrile rubber (a) containing an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit in a proportion of 5 to 60% by weight and having an iodine value of 120 or less.
- a silica (b) having a specific surface area of 70 m 2 / g or less and a polyamine crosslinking agent (c), and the polyamine crosslinking with respect to 100 parts by weight of the carboxyl group-containing highly saturated nitrile rubber (a).
- a nitrile rubber composition is provided in which the content of the agent (c) is 0.1 to 20 parts by weight.
- the content of the silica (b) is preferably 10 to 100 parts by weight with respect to 100 parts by weight of the carboxyl group-containing highly saturated nitrile rubber (a).
- the silica (b) preferably has a specific surface area of 60 m 2 / g or less.
- the carboxyl group-containing highly saturated nitrile rubber (a) comprises 5 to 60% by weight of an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit and an ⁇ , ⁇ -ethylenically unsaturated dicarboxylic acid.
- the nitrile rubber composition of the present invention preferably contains 0.1 to 30% by weight of acid monoester monomer units and 10 to 80% by weight of conjugated diene monomer units.
- the nitrile rubber composition of the present invention preferably further contains a basic crosslinking accelerator.
- the nitrile rubber composition of the present invention preferably further contains a silane coupling agent (d).
- the nitrile rubber composition of the present invention preferably further contains a plasticizer.
- the plasticizer is preferably at least one selected from trimellitic acid plasticizers, ether ester plasticizers, and adipic acid ester plasticizers.
- a rubber cross-linked product obtained by cross-linking the above nitrile rubber composition.
- the nitrile rubber composition of the present invention contains a carboxyl group-containing highly saturated nitrile rubber (a) containing an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit in a proportion of 5 to 60% by weight and having an iodine value of 120 or less. ), A silica (b) having a specific surface area of 70 m 2 / g or less, and a polyamine-based crosslinking agent (c), and the polyamine system based on 100 parts by weight of the carboxyl group-containing highly saturated nitrile rubber (a)
- the content of the crosslinking agent (c) is 0.1 to 20 parts by weight.
- Carboxyl group-containing highly saturated nitrile rubber (a) The carboxyl group-containing highly saturated nitrile rubber (a) (hereinafter simply referred to as “a”, “ ⁇ ”) containing an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit used in the present invention in a proportion of 5 to 60% by weight and having an iodine value of 120 or less.
- “Carboxyl group-containing highly saturated nitrile rubber (a)” is sometimes referred to as an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer, a carboxyl group-containing monomer, and an optional copolymerizable monomer. It is a rubber having an iodine value of 120 or less, obtained by copolymerizing other monomers.
- the ⁇ , ⁇ -ethylenically unsaturated nitrile monomer is not particularly limited as long as it is an ⁇ , ⁇ -ethylenically unsaturated compound having a nitrile group.
- acrylonitrile; ⁇ -chloroacrylonitrile, ⁇ -bromoacrylonitrile, etc. ⁇ -halogenoacrylonitrile, ⁇ -alkylacrylonitrile such as methacrylonitrile, and the like Among these, acrylonitrile and methacrylonitrile are preferable, and acrylonitrile is more preferable.
- the ⁇ , ⁇ -ethylenically unsaturated nitrile monomer may be used alone or in combination of two or more.
- the content of the ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit is 5 to 60% by weight, preferably 10 to 50% by weight, more preferably 15 to 50% by weight based on the total monomer units. is there. If the content of the ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit is too small, the resulting rubber cross-linked product will be inferior in oil resistance, while if it is too much, cold resistance will be reduced.
- the carboxyl group-containing monomer can be copolymerized with an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer and has at least one unsubstituted (free) carboxyl group that is not esterified. If it is a monomer, it will not specifically limit.
- a carboxyl group-containing monomer By using a carboxyl group-containing monomer, a carboxyl group can be introduced into the nitrile rubber.
- Examples of the carboxy group-containing monomer used in the present invention include ⁇ , ⁇ -ethylenically unsaturated monocarboxylic acid monomers, ⁇ , ⁇ -ethylenically unsaturated polycarboxylic acid monomers, and ⁇ , ⁇ -Ethylenically unsaturated dicarboxylic acid monoester monomers and the like.
- the carboxyl group-containing monomer also includes monomers in which the carboxyl group of these monomers forms a carboxylate.
- an anhydride of an ⁇ , ⁇ -ethylenically unsaturated polyvalent carboxylic acid can also be used as a carboxyl group-containing monomer because it forms a carboxyl group by cleaving the acid anhydride group after copolymerization.
- Examples of the ⁇ , ⁇ -ethylenically unsaturated monocarboxylic acid monomer include acrylic acid, methacrylic acid, ethyl acrylic acid, crotonic acid, and cinnamic acid.
- Examples of the ⁇ , ⁇ -ethylenically unsaturated polyvalent carboxylic acid monomer include butenedionic acid such as fumaric acid and maleic acid, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, allylmalonic acid, and teraconic acid.
- Examples of the anhydride of ⁇ , ⁇ -unsaturated polyvalent carboxylic acid include maleic anhydride, itaconic anhydride, citraconic anhydride, and the like.
- maleic acid monoalkyl esters such as monomethyl maleate, monoethyl maleate, monopropyl maleate, mono n-butyl maleate; monocyclopentyl maleate, Maleic acid monocycloalkyl esters such as monocyclohexyl maleate and monocycloheptyl maleate; Monoalkyl cycloalkyl esters of maleic acid such as monomethylcyclopentyl maleate and monoethylcyclohexyl maleate; Monomethyl fumarate, monoethyl fumarate and monofumarate Monoalkyl esters of fumaric acid such as propyl and mono-n-butyl fumarate; fumaric acid such as monocyclopentyl fumarate, monocyclohexyl fumarate and monocycloheptyl fumarate Monocycloalkyl esters of fumaric acid such as monocyclopentyl fumarate, monocyclohexyl fumarate and monocycloheptyl fum
- the carboxyl group-containing monomers may be used singly or in combination.
- ⁇ , ⁇ -ethylenically unsaturated dicarboxylic acid monoester monomer is preferable because the effects of the present invention become more remarkable, and ⁇ , ⁇ -ethylenically unsaturated dicarboxylic acid monoalkyl ester monomer are more preferred, maleic acid monoalkyl esters are more preferred, and mono-n-butyl maleate is particularly preferred.
- the number of carbon atoms in the alkyl group of the alkyl ester is preferably 2-8.
- the content of the carboxyl group-containing monomer unit is preferably 0.1 to 30% by weight, more preferably 1 to 30% by weight, more preferably 1 to 20% by weight, based on the total monomer units. It is preferably 1 to 15% by weight.
- the carboxyl group-containing highly saturated nitrile rubber (a) used in the present invention preferably also contains a conjugated diene monomer unit so that the resulting rubber cross-linked product has rubber elasticity.
- conjugated diene monomer forming the conjugated diene monomer unit examples include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, chloroprene and the like having 4 to 4 carbon atoms. 6 conjugated diene monomers are preferred, 1,3-butadiene and isoprene are more preferred, and 1,3-butadiene is particularly preferred.
- the conjugated diene monomer may be used alone or in combination of two or more.
- the content of the conjugated diene monomer unit is preferably 10 to 80% by weight, more preferably 25 to 75% by weight, and still more preferably based on the total monomer units. It is 40 to 70% by weight, particularly preferably 50 to 70% by weight.
- the carboxyl group-containing highly saturated nitrile rubber (a) used in the present invention is added to the ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit, the carboxyl group-containing monomer unit, and the conjugated diene monomer unit.
- it may contain other monomer units copolymerizable with the monomers forming these. Examples of such other monomers include ⁇ , ⁇ -ethylenically unsaturated monocarboxylic acid ester monomers, ethylene, ⁇ -olefin monomers, aromatic vinyl monomers, fluorine-containing vinyl monomers, Examples thereof include copolymerizable anti-aging agents.
- Examples of ⁇ , ⁇ -ethylenically unsaturated monocarboxylic acid ester monomers include methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, n-dodecyl acrylate, methyl methacrylate, and ethyl methacrylate.
- (Meth) acrylic acid ester having an alkyl group having 1 to 18 carbon atoms (abbreviation of “methacrylic acid ester and acrylic acid ester”; the same shall apply hereinafter); methoxymethyl acrylate, methoxyethyl acrylate, ethoxypropyl acrylate, (Meth) acrylic acid ester having a C2-C18 alkoxyalkyl group such as methoxybutyl acrylate, ethoxydodecyl acrylate, methoxyethyl methacrylate, methoxybutyl methacrylate, ethoxypentyl methacrylate; ⁇ -cyanoethyl acrylate; (Meth) acrylic acid esters having a cyanoalkyl group having 2 to 12 carbon atoms such as ⁇ -cyanoethyl tacrylate and cyanobutyl methacrylate; 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyeth
- (meth) acrylic acid esters having an alkoxyalkyl group having 2 to 18 carbon atoms are preferred, methoxyethyl acrylate and methoxyethyl methacrylate are more preferred, and methoxyethyl acrylate is particularly preferred.
- the ⁇ -olefin monomer preferably has 3 to 12 carbon atoms, and examples thereof include propylene, 1-butene, 4-methyl-1-pentene, 1-hexene and 1-octene.
- aromatic vinyl monomer examples include styrene, ⁇ -methylstyrene, vinyl pyridine and the like.
- fluorine-containing vinyl monomer examples include fluoroethyl vinyl ether, fluoropropyl vinyl ether, o-trifluoromethylstyrene, vinyl pentafluorobenzoate, difluoroethylene, and tetrafluoroethylene.
- copolymerizable anti-aging agents examples include N- (4-anilinophenyl) acrylamide, N- (4-anilinophenyl) methacrylamide, N- (4-anilinophenyl) cinnamamide, N- (4-anilino). Phenyl) crotonamide, N-phenyl-4- (3-vinylbenzyloxy) aniline, N-phenyl-4- (4-vinylbenzyloxy) aniline and the like.
- the content of other monomer units is preferably 50% by weight or less, more preferably 40% by weight or less, based on all monomer units constituting the carboxyl group-containing highly saturated nitrile rubber (a). Preferably it is 10 weight% or less.
- the iodine value of the carboxyl group-containing highly saturated nitrile rubber (a) is 120 or less, preferably 60 or less, more preferably 40 or less, and particularly preferably 30 or less.
- the polymer Mooney viscosity (ML 1 + 4 , 100 ° C.) of the carboxyl group-containing highly saturated nitrile rubber (a) is preferably 10 to 200, more preferably 15 to 150, still more preferably 15 to 100, and particularly preferably 30 to 70. It is.
- the polymer Mooney viscosity of the carboxyl group-containing highly saturated nitrile rubber (a) in the above range, the resulting rubber cross-linked product can be made excellent in workability while having good mechanical properties. .
- the carboxyl group content in the carboxyl group-containing highly saturated nitrile rubber (a), that is, the number of moles of carboxyl groups per 100 g of the carboxyl group-containing highly saturated nitrile rubber (a) is preferably 5 ⁇ 10 ⁇ 4 to 5 ⁇ 10 ⁇ 1 ephr, more preferably 1 ⁇ 10 ⁇ 3 to 1 ⁇ 10 ⁇ 1 ephr, and particularly preferably 5 ⁇ 10 ⁇ 3 to 6 ⁇ 10 ⁇ 2 ephr.
- the carboxyl group content of the carboxyl group-containing highly saturated nitrile rubber (a) within the above range, the scorch stability of the nitrile rubber composition is improved, and the mechanical properties and compression resistance of the resulting rubber crosslinked product are improved. Distortion can be further improved.
- the method for producing the carboxyl group-containing highly saturated nitrile rubber (a) used in the present invention is not particularly limited, but the above-mentioned monomers are copolymerized and, if necessary, the carbon-carbon dicarboxylic acid in the resulting copolymer. It can be produced by hydrogenating heavy bonds.
- the polymerization method is not particularly limited and may be a known emulsion polymerization method or solution polymerization method. From the viewpoint of industrial productivity, the emulsion polymerization method is preferable. In emulsion polymerization, in addition to an emulsifier, a polymerization initiator, and a molecular weight modifier, a commonly used polymerization auxiliary material can be used.
- nonionic emulsifiers such as polyoxyethylene alkyl ether, polyoxyethylene alkyl phenol ether, polyoxyethylene alkyl ester, polyoxyethylene sorbitan alkyl ester; myristic acid, palmitic acid, oleic acid And salts of fatty acids such as linolenic acid, alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate, anionic emulsifiers such as higher alcohol sulfates and alkylsulfosuccinates; sulfoesters of ⁇ , ⁇ -unsaturated carboxylic acids, ⁇ , ⁇ -unsaturated carboxylic acid sulfate esters, sulfoalkyl aryl ethers and other copolymerizable emulsifiers.
- the amount of the emulsifier added is preferably 0.1 to 10 parts
- the polymerization initiator is not particularly limited as long as it is a radical initiator, but inorganic peroxides such as potassium persulfate, sodium persulfate, ammonium persulfate, potassium perphosphate, hydrogen peroxide; t-butyl peroxide, cumene Hydroperoxide, p-menthane hydroperoxide, di-t-butyl peroxide, t-butylcumyl peroxide, acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, dibenzoyl peroxide, 3, 5, 5 Organic peroxides such as trimethylhexanoyl peroxide and t-butylperoxyisobutyrate; azobisisobutyronitrile, azobis-2,4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, methyl azobisisobutyrate, etc.
- inorganic peroxides
- polymerization initiators can be used alone or in combination of two or more.
- an inorganic or organic peroxide is preferable.
- a peroxide is used as the polymerization initiator, it can be used as a redox polymerization initiator in combination with a reducing agent such as sodium bisulfite or ferrous sulfate.
- the addition amount of the polymerization initiator is preferably 0.01 to 2 parts by weight with respect to 100 parts by weight of the monomer used for the polymerization.
- Water is usually used as the emulsion polymerization medium.
- the amount of water is preferably 80 to 500 parts by weight, more preferably 80 to 300 parts by weight with respect to 100 parts by weight of the monomer used for the polymerization.
- polymerization auxiliary materials such as a stabilizer, a dispersant, a pH adjuster, an oxygen scavenger, and a particle size adjuster can be used as necessary. In using these, neither the kind nor the usage-amount is specifically limited.
- the obtained copolymer may be subjected to hydrogenation (hydrogenation reaction) as necessary.
- Hydrogenation may be carried out by a known method. After coagulating a latex of a copolymer obtained by emulsion polymerization, an oil layer hydrogenation method in which hydrogenation is performed in an oil layer, or a latex of the obtained copolymer is hydrogenated as it is. And water layer hydrogenation method.
- the copolymer latex prepared by emulsion polymerization is preferably dissolved in an organic solvent through salting out, coagulation with alcohol, filtration and drying. Subsequently, a hydrogenation reaction (oil layer hydrogenation method) is performed, and the resulting hydride is poured into a large amount of water, solidified, filtered, and dried to obtain a carboxyl group-containing highly saturated nitrile rubber (a). .
- a known coagulant such as sodium chloride, calcium chloride, aluminum sulfate can be used. Moreover, it may replace with solidification by salting out and may perform coagulation using alcohol, such as methanol.
- the solvent for the oil layer hydrogenation method is not particularly limited as long as it is a liquid organic compound that dissolves the copolymer obtained by emulsion polymerization, but benzene, chlorobenzene, toluene, xylene, hexane, cyclohexane, tetrahydrofuran, methyl ethyl ketone, ethyl acetate. Cyclohexanone and acetone are preferably used.
- any known selective hydrogenation catalyst can be used without limitation.
- Palladium-based catalysts and rhodium-based catalysts are preferable, and palladium-based catalysts (such as palladium acetate, palladium chloride and palladium hydroxide) are preferred. More preferred. Two or more of these may be used in combination. In this case, it is preferable to use a palladium-based catalyst as the main active ingredient.
- These catalysts are usually used by being supported on a carrier.
- the carrier include silica, silica-alumina, alumina, diatomaceous earth, activated carbon and the like.
- the amount of catalyst used is preferably 10 to 5000 ppm by weight, more preferably 100 to 3000 ppm by weight, based on the copolymer.
- the latex of the copolymer prepared by the emulsion polymerization is diluted with water as necessary to perform a hydrogenation reaction.
- the water layer hydrogenation method is a water layer direct hydrogenation method in which hydrogen is supplied to a reaction system in the presence of a hydrogenation catalyst to perform hydrogenation, and reduction and hydrogenation are performed in the presence of an oxidizing agent, a reducing agent and an activator.
- An aqueous layer indirect hydrogenation method can be mentioned, and among these, the aqueous layer direct hydrogenation method is preferable.
- the concentration of the copolymer in the aqueous layer is preferably 40% by weight or less in order to prevent aggregation.
- a hydrogenation catalyst will not be specifically limited if it is a compound which is hard to decompose
- the palladium catalyst include palladium salts of carboxylic acids such as formic acid, propionic acid, lauric acid, succinic acid, oleic acid, and phthalic acid; palladium chloride, dichloro (cyclooctadiene) palladium, dichloro (norbornadiene) palladium, Palladium chloride such as ammonium hexachloropalladium (IV); Iodide such as palladium iodide; Palladium sulfate dihydrate and the like.
- palladium salts of carboxylic acids, dichloro (norbornadiene) palladium and ammonium hexachloropalladium (IV) are particularly preferred.
- the amount of the hydrogenation catalyst used may be appropriately determined, but is preferably 5 to 6000 ppm by weight, more preferably 10 to 4000 ppm by weight, based on the copolymer obtained by polymerization.
- the hydrogenation catalyst in the latex is removed after completion of the hydrogenation reaction.
- an adsorbent such as activated carbon or ion exchange resin is added to adsorb the hydrogenation catalyst with stirring, and then the latex is filtered or centrifuged. It is also possible to leave it in the latex without removing the hydrogenation catalyst.
- the latex after the hydrogenation reaction thus obtained is subjected to coagulation by salting out, filtration, drying, and the like, whereby a carboxyl group-containing highly saturated nitrile rubber (a ) Can be obtained.
- a carboxyl group-containing highly saturated nitrile rubber (a ) can be obtained.
- the filtration and drying steps subsequent to coagulation can be performed by known methods.
- the nitrile rubber composition of the present invention has a silica (b) having a specific surface area of 70 m 2 / g or less (hereinafter simply referred to as “silica (b ) ”))).
- silica (b) having a specific surface area of 70 m 2 / g or less
- the above-mentioned carboxyl group-containing highly saturated nitrile rubber (a) and silica (b) having a specific surface area of 70 m 2 / g or less are used in combination to crosslink the rubber, In this case, the dynamic heat generation can be kept low while improving the normal state physical properties.
- the specific surface area of the silica (b) mentioned above shows the average value of the specific surface area of each particle, and therefore the specific surface area of some particles of the silica (b) exceeds 70 m 2 / g. Even so, the average value of the specific surface area of each particle constituting the silica (b) may be 70 m 2 / g or less.
- Silica (b) used in the present invention is not particularly limited as long as it has a specific surface area of 70 m 2 / g or less, but is not limited to natural silica such as quartz powder and quartzite powder; silicic anhydride (silica gel, aerosil, etc.) ), Synthetic silica such as hydrous silicic acid; among these, synthetic silica is preferable from the viewpoint that dynamic heat generation can be further reduced.
- the specific surface area of the silica (b) used in the present invention is 70 m 2 / g or less, preferably 65 m 2 / g or less, more preferably 60 m 2 / g or less.
- the lower limit of the specific surface area of the silica (b) used in the present invention is not particularly limited, but is preferably 20 m 2 / g or more, more preferably 25 m 2 / g or more, and even more preferably 30 m 2 / g or more. is there. If the specific surface area is too large, the effect of lowering the dynamic heat generation cannot be obtained, so that the dynamic heat generation of the resulting rubber cross-linked product becomes large.
- the specific surface area of silica (b) can be measured, for example, by the BET method according to ASTM D3037-81.
- Specific examples of silica (b) include trade name “Nipsil EL” (manufactured by Tosoh Silica, BET specific surface area: 48 m 2 / g), trade name “Nipsil E-74P” (manufactured by Tosoh Silica, BET ratio). Surface area: 45 m 2 / g), and trade name “Hi-Sil 532EP” (manufactured by PPG Industries, BET specific surface area: 55 m 2 / g).
- the amount of silica (b) in the nitrile rubber composition of the present invention is preferably 10 to 100 parts by weight, more preferably 20 parts per 100 parts by weight of the carboxyl group-containing highly saturated nitrile rubber (a). Is 90 parts by weight, more preferably 30-80 parts by weight.
- Polyamine crosslinking agent (c) The nitrile rubber composition of the present invention contains a polyamine-based crosslinking agent (c) in addition to the above-described carboxyl group-containing highly saturated nitrile rubber (a) and silica (b).
- a polyamine-based crosslinking agent (c) As the crosslinking agent, the compression set resistance of the resulting rubber crosslinked product can be appropriately improved.
- the polyamine-based crosslinking agent (c) is not particularly limited as long as it is a compound having two or more amino groups or a compound having two or more amino groups at the time of crosslinking.
- polyamine crosslinking agent (c) examples include fats such as hexamethylene diamine, hexamethylene diamine carbamate, N, N-dicinnamylidene-1,6-hexane diamine, tetramethylene pentamine, and hexamethylene diamine cinnamaldehyde adduct.
- Aromatic polyamines such as diamine, 1,3,5-benzenetriamine; isophthalic acid dihydrazide, terephthalic acid dihydrazide, phthalic acid dihydrazide, 2,6-naphthalenedicarboxylic acid dihydrazide, naphthalene acid dihydrazide, ox
- aliphatic polyvalent amines and aromatic polyvalent amines are preferable from the viewpoint that the effects of the present invention can be made more remarkable, and hexamethylenediamine carbamate and 2,2-bis [ 4- (4-Aminophenoxy) phenyl] propane is more preferred, and hexamethylenediamine carbamate is particularly preferred.
- the content of the polyamine crosslinking agent (c) in the nitrile rubber composition of the present invention is not particularly limited, but is preferably 0.1 to 20 with respect to 100 parts by weight of the carboxyl group-containing highly saturated nitrile rubber (a). Parts by weight, more preferably 0.2 to 15 parts by weight, still more preferably 0.5 to 10 parts by weight.
- the content of the polyamine-based crosslinking agent (c) in the above range sufficient crosslinking can be achieved in the case of a rubber crosslinked product, and the mechanical properties of the resulting rubber crosslinked product are better. Can be.
- Silane coupling agent (d) The nitrile rubber composition of the present invention contains a silane coupling agent (d) in addition to the above-described carboxyl group-containing highly saturated nitrile rubber (a), silica (b), and polyamine-based crosslinking agent (c). Preferably it is. By blending the silane coupling agent (d), when a rubber cross-linked product is obtained, the tensile strength of the resulting rubber cross-linked product can be further improved.
- the silane coupling agent (d) is not particularly limited, and specific examples thereof include ⁇ -mercaptopropyltrimethoxysilane, ⁇ -mercaptomethyltrimethoxylane, ⁇ -mercaptomethyltriethoxylane, and ⁇ -mercaptohexamethyldi.
- Silane coupling agents containing sulfur such as silazane, bis (3-triethoxysilylpropyl) tetrasulfane, bis (3-triethoxysilylpropyldisulfane); ⁇ -glycidoxypropyltrimethoxysilane, ⁇ -glycine Epoxy group-containing silane coupling agents such as sidoxypropylmethyldimethoxysilane, ⁇ - (3,4-epoxycyclohexyl) ethyltrimethoxysilane, ⁇ -mercaptopropyltrimethoxysilane, ⁇ -glycidoxypropylmethyldiethoxysilane; N- ( ⁇ - Minoethyl) - ⁇ -aminopropyltrimethoxysilane, ⁇ -aminopropyltrimethoxysilane, ⁇ -aminopropyltriethoxysilane, N-2- (aminoethyl) -3-amin
- Alkyl group-containing silane coupling agents such as acetoalkoxyaluminum diisopropylate; isopropyltriisostearoyl titanate, isopropyltris (dioctylpyrophosphate) titanate, isopropyltri (N-aminoethyl-aminoethyl) Titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (di Titanate coupling agents such as rididyl) phosphite titanate, bis (dioctyl pyrophosphate) oxyacetate titanate, bis (dioctyl pyrophosphate) ethylene titanate, tetraisopropyl bis (dioctyl phosphite) titanate, isopropyl triisostea
- silane coupling agents and epoxy group-containing silane coupling agents are preferred from the viewpoint of high addition effect, and ⁇ -aminopropyltrimethoxysilane and ⁇ -glycidoxypropyltrimethoxysilane are preferred. Is more preferable.
- the surface of the silica (b) may be preliminarily surface-treated with the silane coupling agent, or without surface treatment in advance. You may use it in the form which mix
- the compounding amount of the silane coupling agent (d) in the nitrile rubber composition of the present invention is preferably 0.1 to 5 parts by weight, more preferably 0.8 parts per 100 parts by weight of silica (b). 2 to 3 parts by weight, more preferably 0.3 to 1.5 parts by weight.
- the nitrile rubber composition of the present invention comprises the above-described carboxyl group-containing highly saturated nitrile rubber (a), silica (b), polyamine-based crosslinking agent (c), and silane compounded as necessary.
- the coupling agent (d) it is preferable to further contain a basic crosslinking accelerator from the viewpoint that the effects of the present invention can be made more remarkable.
- basic crosslinking accelerators include compounds represented by the following general formula (1), basic crosslinking accelerators having a cyclic amidine structure, guanidine basic crosslinking accelerators, and aldehyde amine basic crosslinking accelerators. Agents and the like.
- R 1 and R 2 may each independently have an alkyl group having 1 to 12 carbon atoms which may have a substituent, or may have a substituent.
- It is a cycloalkyl group having 5 to 12 carbon atoms.
- R 1 and R 2 are each an optionally substituted alkyl group having 1 to 12 carbon atoms or an optionally substituted cycloalkyl group having 5 to 12 carbon atoms.
- a cycloalkyl group having 5 to 12 carbon atoms which may have a group is preferable, and a cycloalkyl group having 5 to 8 carbon atoms which may have a substituent is particularly preferable.
- R 1 and R 2 are preferably not substituted.
- R 1 and R 2 have a substituent include a hydroxyl group, an alkoxy group, an alkoxycarbonyl group, an amino group, and a halogen atom.
- a compound represented by the following general formula (2) is more preferable from the viewpoint that processability and scorch stability can be further improved.
- R 3 and R 4 are each independently a cycloalkyl group having 5 to 8 carbon atoms which may have a substituent.
- R 3 and R 4 are cycloalkyl groups having 5 to 8 carbon atoms which may have a substituent, but may be cycloalkyl groups which may have a substituent having 5 or 6 carbon atoms. Is preferable, and a cycloalkyl group which may have a substituent having 6 carbon atoms is more preferable. R 3 and R 4 preferably have no substituent.
- R 3 and R 4 have a substituent include a hydroxyl group, an alkoxy group, an alkoxycarbonyl group, an amino group, and a halogen atom.
- Specific examples of the compound represented by the general formula (1) include dicycloalkylamines such as dicyclopentylamine, dicyclohexylamine and dicycloheptylamine; N-methylcyclopentylamine, N-butylcyclopentylamine and N-heptyl.
- Examples of the basic crosslinking accelerator having a cyclic amidine structure include 1,8-diazabicyclo [5,4,0] undecene-7 (hereinafter sometimes abbreviated as “DBU”) and 1,5-diazabicyclo [4, 3,0] nonene-5 (hereinafter sometimes abbreviated as “DBN”), 1-methylimidazole, 1-ethylimidazole, 1-phenylimidazole, 1-benzylimidazole, 1,2-dimethylimidazole, 1-ethyl- 2-methylimidazole, 1-methoxyethylimidazole, 1-phenyl-2-methylimidazole, 1-benzyl-2-methylimidazole, 1-methyl-2-phenylimidazole, 1-methyl-2-benzylimidazole, 1,4 -Dimethylimidazole, 1,5-dimethylimidazole, 1,2,4-trimethylimidazole, 1,4- Methyl-2-ethylimidazole,
- 1,8-diazabicyclo [5,4,0] undecene-7 and 1,5-diazabicyclo [4,3,0] nonene-5 are preferred, , 8-diazabicyclo [5,4,0] undecene-7 is more preferred.
- the guanidine-based basic crosslinking accelerator include tetramethylguanidine, tetraethylguanidine, diphenylguanidine, 1,3-di-ortho-tolylguanidine, orthotolyl biguanide and the like.
- aldehyde amine basic crosslinking accelerator include n-butyraldehyde aniline and acetaldehyde ammonia.
- guanidine basic crosslinking accelerators compounds represented by the above general formula (1), guanidine basic crosslinking accelerators, and basic crosslinking accelerators having a cyclic amidine structure are preferable.
- a compound represented by the formula and a basic crosslinking accelerator having a cyclic amidine structure are more preferred.
- the compound represented by the general formula (1) may be a mixture of an alkylene glycol or an alcohol such as an alkyl alcohol having 5 to 20 carbon atoms, and an inorganic acid and / or an organic acid. May be included. Further, as the compound represented by the general formula (1), a salt is formed by the compound represented by the general formula (1) and the inorganic acid and / or organic acid, and a complex is formed with alkylene glycol. It may be.
- the basic crosslinking accelerator having a cyclic amidine structure may form a salt with an organic carboxylic acid or an alkyl phosphoric acid.
- the blending amount in the nitrile rubber composition of the present invention is preferably 0.1 to 20 parts by weight with respect to 100 parts by weight of the carboxyl group-containing highly saturated nitrile rubber (a). More preferably 0.2 to 15 parts by weight, still more preferably 0.5 to 10 parts by weight.
- the nitrile rubber composition of the present invention includes a compounding agent usually used in the rubber field, for example, metal oxides such as zinc oxide and magnesium oxide, ⁇ , such as zinc methacrylate and zinc acrylate, ⁇ -ethylenically unsaturated carboxylic acid metal salt, co-crosslinking agent, crosslinking aid, crosslinking retarder, anti-aging agent, antioxidant, light stabilizer, scorch inhibitor such as primary amine, activator such as diethylene glycol, plastic Agents, processing aids, lubricants, adhesives, lubricants, flame retardants, antifungal agents, acid acceptors, antistatic agents, pigments, foaming agents and the like can be blended.
- the compounding amount of these compounding agents is not particularly limited as long as it does not impair the object and effect of the present invention, and an amount corresponding to the compounding purpose can be blended.
- the co-crosslinking agent is not particularly limited, but is preferably a low molecular or high molecular compound having a plurality of radical-reactive unsaturated groups in the molecule.
- a polyfunctional vinyl compound such as divinylbenzene or divinylnaphthalene; Isocyanurates such as allyl isocyanurate and trimethallyl isocyanurate; cyanurates such as triallyl cyanurate; maleimides such as N, N′-m-phenylene dimaleimide; diallyl phthalate, diallyl isophthalate, diallyl maleate, diallyl Allyl esters of polyvalent acids such as fumarate, diallyl sebacate, triallyl phosphate; diethylene glycol bisallyl carbonate; ethylene glycol diallyl ether, triallyl ether of trimethylolpropane, pentaerythritol Allyl ethers such as partial trityl ethers of trit; ally
- the plasticizer is not particularly limited, but trimellitic acid plasticizer, pyromellitic acid plasticizer, ether ester plasticizer, polyester plasticizer, phthalic acid plasticizer, adipate ester plasticizer, phosphoric acid
- trimellitic acid plasticizer pyromellitic acid plasticizer
- ether ester plasticizer polyester plasticizer
- phthalic acid plasticizer adipate ester plasticizer
- phosphoric acid An ester plasticizer, a sebacic acid ester plasticizer, an alkyl sulfonic acid ester compound plasticizer, an epoxidized vegetable oil plasticizer, or the like can be used.
- trimellitic acid tri-2-ethylhexyl trimellitic acid isononyl ester, trimellitic acid mixed linear alkyl ester, dipentaerythritol ester, pyromellitic acid 2-ethylhexyl ester, polyether ester (molecular weight 300 to About 5,000), bis [2- (2-butoxyethoxy) ethyl adipate], dioctyl adipate, polyester based on adipic acid (molecular weight about 300 to 5000), dioctyl phthalate, diisononyl phthalate, dibutyl phthalate, phosphoric acid
- examples include tricresyl, dibutyl sebacate, alkyl sulfonic acid phenyl ester, epoxidized soybean oil, diheptanoate, di-2-ethylhexanoate, didecanoate and the like. These can be used alone or in combination.
- the nitrile rubber composition of the present invention may contain a rubber other than the carboxyl group-containing highly saturated nitrile rubber (a) as long as the effects of the present invention are not impaired.
- rubbers other than the carboxyl group-containing highly saturated nitrile rubber (a) include acrylic rubber, ethylene-acrylic acid copolymer rubber, fluorine rubber, styrene-butadiene copolymer rubber, polybutadiene rubber, ethylene-propylene copolymer rubber, Mention may be made of ethylene-propylene-diene terpolymer rubber, epichlorohydrin rubber, urethane rubber, chloroprene rubber, silicone rubber, fluorosilicone rubber, chlorosulfonated polyethylene rubber, natural rubber and polyisoprene rubber.
- the blending amount is preferably 30 parts by weight or less, and 20 parts by weight or less with respect to 100 parts by weight of the carboxyl group-containing highly saturated nitrile rubber (a). Is more preferable, and 10 parts by weight or less is particularly preferable.
- the nitrile rubber composition of the present invention is prepared by mixing the above components, preferably in a non-aqueous system.
- the method for preparing the nitrile rubber composition of the present invention is not limited, but usually the components excluding the cross-linking agent and heat-unstable components (for example, cross-linking aid) are used as Banbury mixers, intermixers, kneaders, etc. After first kneading with this mixer, it can be prepared by transferring to a roll or the like and adding a cross-linking agent or a heat-unstable component, followed by secondary kneading.
- Cross-linked rubber The cross-linked rubber of the present invention is obtained by cross-linking the nitrile rubber composition of the present invention described above.
- the rubber cross-linked product of the present invention uses the nitrile rubber composition of the present invention and is molded by a molding machine corresponding to a desired shape, for example, an extruder, an injection molding machine, a compressor, a roll, etc., and heated. It can be produced by carrying out a crosslinking reaction and fixing the shape as a crosslinked product. In this case, crosslinking may be performed after molding in advance, or crosslinking may be performed simultaneously with molding.
- the molding temperature is usually 10 to 200 ° C, preferably 25 to 120 ° C.
- the crosslinking temperature is usually 100 to 200 ° C., preferably 130 to 190 ° C.
- the crosslinking time is usually 1 minute to 24 hours, preferably 2 minutes to 1 hour.
- secondary cross-linking may be performed by heating.
- a heating method a general method used for crosslinking of rubber such as press heating, steam heating, oven heating, and hot air heating may be appropriately selected.
- the rubber cross-linked product of the present invention obtained in this way is obtained by cross-linking the nitrile rubber composition of the present invention described above, and has good normal physical properties and low dynamic heat generation. is there.
- the rubber cross-linked product of the present invention makes use of such characteristics, and O-rings, packings, diaphragms, dampers, oil seals, shaft seals, bearing seals, well head seals, shock absorber seals, pneumatic equipment seals, Fluorocarbon or fluorohydrocarbon or carbon dioxide sealing seals used in air conditioner cooling units and air conditioner refrigerator compressors, supercritical carbon dioxide or subcritical carbon dioxide used in cleaning media for precision cleaning Seals for seals, seals for rolling devices (rolling bearings, automotive hub units, automotive water pumps, linear guide devices, ball screws, etc.), various seals such as valves and valve seats, BOPs (Blow Out Presenter), platters, etc.
- Intake manifold hole Intake manifold gasket attached to the connecting portion between the cylinder head and the cylinder head, cylinder head gasket attached to the connecting portion between the cylinder block and the cylinder head, rocker cover gasket attached to the connecting portion between the rocker cover and the cylinder head, Oil pan gasket attached to the connecting part of oil pan and cylinder block or transmission case, gasket for fuel cell separator attached between a pair of housings sandwiching a unit cell having a positive electrode, electrolyte plate and negative electrode, and hard disk drive
- Various gaskets such as top cover gaskets; various rolls such as printing rolls, iron-making rolls, paper-making rolls, industrial rolls, and office machine rolls; flat belts (film core flat belts, cord flat belts, laminated flat belts) , Single flat belt, etc.), V belt (wrapped V belt, low edge V belt, etc.), V ribbed belt (single V ribbed belt, double V ribbed belt, wrapped V ribbed belt, back rubber V ribbed belt
- composition of carboxyl group-containing highly saturated nitrile rubber The content ratio of each monomer unit constituting the carboxyl group-containing highly saturated nitrile rubber was measured by the following method. That is, the content ratio of mono-n-butyl maleate units was determined by determining the number of moles of carboxyl groups relative to 100 g of carboxyl group-containing highly saturated nitrile rubber after hydrogenation by the above-mentioned “carboxyl group content” measurement method. The number was calculated by converting it to the amount of mono n-butyl maleate units.
- the content ratio of 1,3-butadiene units was calculated by measuring the iodine value of the carboxyl group-containing nitrile rubber before the hydrogenation reaction by the following method.
- the content ratio of the acrylonitrile unit was calculated by measuring the nitrogen content in the carboxyl-containing highly saturated nitrile rubber after hydrogenation according to Kjeldahl method according to JIS K6384.
- the content ratio of the methoxyethyl acrylate unit was calculated as the balance of each monomer unit.
- the iodine value of the highly saturated nitrile rubber containing the iodine value carboxyl group was measured according to JIS K 6235.
- Mooney viscosity The Mooney viscosity (polymer Mooney) of the highly saturated carboxyl group-containing nitrile rubber was measured according to JIS K6300 (unit: [ML 1 + 4 , 100 ° C.]).
- the nitrile rubber composition was placed in a mold having a length of 15 cm, a width of 15 cm, and a depth of 0.2 cm, and press-molded at 170 ° C. for 20 minutes while being pressed at a press pressure of 10 MPa to obtain a sheet-like primary cross-linked product.
- the obtained primary cross-linked product was transferred to a gear-type oven and subjected to secondary cross-linking at 170 ° C. for 4 hours, and the obtained sheet-like rubber cross-linked product was punched with a No. 3 dumbbell to prepare a test piece.
- Exothermic test The exothermic property was evaluated by a flexometer test specified by ASTM D 623-78. Specifically, first, it was placed in a cylindrical mold having a diameter of 17.8 ⁇ 0.15 mm and a depth of 25 ⁇ 0.25 mm, crosslinked at 170 ° C. for 20 minutes, and then subjected to secondary crosslinking at 170 ° C. for 4 hours. By performing, the test piece for a flexometer test was obtained. Then, using a flexometer (GABO meter 4000, manufactured by GABO), an exothermic test was performed by applying a dynamic displacement for 25 minutes under the conditions of a test temperature of 100 ° C., an initial load of 1 MPa, and a dynamic displacement of 4.45 mm.
- a flexometer test specified by ASTM D 623-78. Specifically, first, it was placed in a cylindrical mold having a diameter of 17.8 ⁇ 0.15 mm and a depth of 25 ⁇ 0.25 mm, crosslinked at 170 ° C
- the measurement frequency was 30 Hz.
- the inside of HBU internal calorific value: the difference between the measured temperature inside the test piece and the ambient temperature of 100 ° C. was taken as the exothermic temperature
- Production Example 1 (Production of carboxyl group highly saturated nitrile rubber (a1))
- a reactor 220 parts of ion-exchanged water, 5 parts of a 10% aqueous sodium dodecylbenzenesulfonate solution, 37 parts of acrylonitrile, 4 parts of mono-n-butyl maleate, and 0.75 part of t-dodecyl mercaptan (molecular weight regulator)
- the internal gas was replaced with nitrogen three times, and then 57 parts of 1,3-butadiene was charged.
- the reactor was kept at 10 ° C., 0.06 part of cumene hydroperoxide (polymerization initiator), a reducing agent, and an appropriate amount of chelating agent were charged, and the polymerization reaction was continued while stirring, with a polymerization conversion rate of 40%, 1 part of mono-n-butyl maleate was added at the time of reaching 60%, and when the polymerization conversion rate reached 85%, a hydroquinone aqueous solution (polymerization terminator) having a concentration of 10% by weight was added. The polymerization reaction was stopped by adding parts. Next, the residual monomer was removed at a water temperature of 60 ° C. to obtain a latex of nitrile rubber (solid content concentration: 30% by weight).
- the nitrile rubber latex and palladium catalyst (1 wt%) were added to the autoclave so that the palladium content relative to the dry weight of the rubber contained in the nitrile rubber latex obtained above was 1,000 ppm by weight.
- a solution in which palladium acetate / acetone solution and equal weight of ion exchange water are mixed) is added, and hydrogenation reaction is performed at a hydrogen pressure of 3 MPa and a temperature of 50 ° C. for 6 hours to obtain a carboxyl group-containing highly saturated nitrile rubber (a1) latex. Obtained.
- the resulting latex of carboxyl group-containing highly saturated nitrile rubber (a1) is solidified by adding twice the volume of methanol, filtered to take out a solid (crumb), and vacuum-dried at 60 ° C. for 12 hours. As a result, a carboxyl group-containing highly saturated nitrile rubber (a1) was obtained.
- the obtained carboxyl group-containing highly saturated nitrile rubber (a1) had a carboxyl group content of 0.030 ephr, an iodine value of 9, and a polymer Mooney viscosity [ML 1 + 4 , 100 ° C.] of 44.
- the resulting carboxyl group-containing highly saturated nitrile rubber (a1) was composed of 35.7% by weight of acrylonitrile units, 58.6% by weight of butadiene units (including saturated portions), and 5% mono n-butyl maleate units. 0.7% by weight.
- Production Example 2 (Production of carboxyl group-containing highly saturated nitrile rubber (a2))
- a2 carboxyl group-containing highly saturated nitrile rubber
- 180 parts of ion-exchanged water, 25 parts of a 10% aqueous sodium dodecylbenzenesulfonate solution, 23 parts of acrylonitrile, 6.5 parts of mono n-butyl maleate, 30.5 parts of methoxyethyl acrylate, and t- Dodecyl mercaptan (molecular weight modifier) was charged in the order of 0.65 part, and the internal gas was substituted with nitrogen three times, and then 40 parts of 1,3-butadiene was charged.
- the reactor was kept at 10 ° C., and 0.06 part of cumene hydroperoxide (polymerization initiator), a reducing agent, and an appropriate amount of chelating agent were charged, and the polymerization reaction was continued while stirring, resulting in a polymerization conversion rate of 83%. At that time, 0.1 part of a 10% by weight hydroquinone aqueous solution (polymerization terminator) was added to terminate the polymerization reaction. Next, the residual monomer was removed at a water temperature of 60 ° C. to obtain a latex of nitrile rubber (solid content concentration: 30% by weight).
- the nitrile rubber latex and palladium catalyst (1 wt%) were added to the autoclave so that the palladium content relative to the dry weight of the rubber contained in the nitrile rubber latex obtained above was 1,000 ppm by weight.
- a solution in which palladium acetate / acetone solution and equal weight of ion exchange water are mixed) is added, and hydrogenation reaction is carried out at a hydrogen pressure of 3 MPa and a temperature of 50 ° C. for 6 hours to obtain a carboxyl group-containing highly saturated nitrile rubber (a2) latex. Obtained.
- the resulting latex of carboxyl group-containing highly saturated nitrile rubber (a2) is coagulated by adding 2 volumes of methanol, filtered to take out a solid (crumb), and vacuum-dried at 60 ° C. for 12 hours.
- a carboxyl group-containing highly saturated nitrile rubber (a2) was obtained.
- the obtained carboxyl group-containing highly saturated nitrile rubber (a2) had a carboxyl group content of 0.034 ephr, an iodine value of 9, and a polymer Mooney viscosity [ML 1 + 4 , 100 ° C.] of 41.
- the obtained carboxyl group-containing highly saturated nitrile rubber (a2) has an acrylonitrile unit of 24% by weight, a butadiene unit (including a saturated portion) of 46.6% by weight, and a mono n-butyl maleate unit of 6.5%. % By weight and methoxyethyl acrylate unit 22.9% by weight.
- Production Example 3 (Production of carboxyl group-containing highly saturated nitrile rubber (a3))
- a3 carboxyl group-containing highly saturated nitrile rubber
- nitrile rubber latex and palladium catalyst 1% by weight acetic acid
- the nitrile rubber latex and palladium catalyst 1% by weight acetic acid
- a solution of a mixture of palladium acetone solution and equal weight of ion-exchanged water) was added, and hydrogenation reaction was performed at a hydrogen pressure of 3 MPa and a temperature of 50 ° C. for 6 hours to obtain a latex of carboxyl group-containing highly saturated nitrile rubber (a3). It was.
- the resulting latex of carboxyl group-containing highly saturated nitrile rubber (a3) was coagulated by adding 2 volumes of methanol, filtered to take out a solid (crumb), and this was vacuum dried at 60 ° C. for 12 hours. As a result, a carboxyl group-containing highly saturated nitrile rubber (a3) was obtained.
- the composition of the resulting carboxyl group-containing highly saturated nitrile rubber (a3) was composed of 20.8% by weight of acrylonitrile units, 44.2% by weight of butadiene units (including saturated portions), and mono n-butyl maleate units. It was 4.5% by weight, n-butyl acrylate unit was 30.5% by weight, and iodine value was 10.
- the latex obtained above is added to an aqueous solution of aluminum sulfate in an amount of 3% by weight with respect to the dry weight of the rubber contained in the latex, and the latex is coagulated by stirring and washed with water. After filtration, the mixture was vacuum-dried at 60 ° C. for 12 hours to obtain a nitrile rubber. Then, the obtained nitrile rubber is dissolved in acetone so as to have a concentration of 12%, and this is put into an autoclave. A palladium-silica catalyst is added at 200 ppm by weight with respect to the nitrile rubber, and a hydrogenation reaction is performed at a hydrogen pressure of 3 MPa. I did it.
- the mixture was poured into a large amount of water to coagulate, filtered and dried to obtain a highly saturated nitrile rubber (a'4).
- the composition of the resulting highly saturated nitrile rubber (a′4) was 36.2% by weight of acrylonitrile units, 63.8% by weight of butadiene units (including a saturated portion), and the iodine value was 28. It was. Further, when the carboxyl group content of the highly saturated nitrile rubber (a′4) was measured according to the above method, it was below the detection limit and was substantially free of carboxyl groups.
- Example 1 Using a Banbury mixer, 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a1) obtained in Production Example 1 was added to silica (b1) (trade name “Nipsil EL” manufactured by Tosoh Silica Co., Ltd., BET specific surface area: 48 m.
- trimellitic acid tri-2-ethylhexyl manufactured by ADEKA, trade name “Adekasizer C-8”, plasticizer
- 5 parts 4,4′-di- ( ⁇ , ⁇ -dimethylbenzyl) ) Diphenylamine (trade name “NOCRACK CD”, manufactured by Ouchi Shinsei Chemical Co., Ltd., anti-aging agent) 1.5 parts
- stearic acid 1 part polyoxyethylene alkyl ether phosphate ester (manufactured by Toho Chemical Industry Co., Ltd. 1 part of “Fanol RL210”, a processing aid) was blended and mixed at 50 ° C. for 5 minutes.
- DBU 1,8-diazabicyclo [5,4,0] -undecene-7
- Rhein Chemie trade name “RHENOGRAN XLA-60 (GE2014)”
- DBU 60% including a zinc dialkyl diphosphate salt
- 4 parts of basic crosslinking accelerator hexamethylenediamine carbamate
- hexamethylenediamine carbamate manufactured by DuPont Dow Elastomer, trade name “Diak # 1”
- a nitrile rubber composition was obtained by blending and kneading 2.4 parts of a polyamine crosslinking agent belonging to a polyvalent amine.
- Example 2 A nitrile rubber composition and a nitrile rubber composition were prepared in the same manner as in Example 1 except that 1 part of 3-aminopropyltriethoxysilane (manufactured by Toray Dow Corning, trade name “Z-6011 SILANE”, silane coupling agent) was blended. A rubber cross-linked product was prepared and evaluated in the same manner as in Example 1. The addition timing of 3-aminopropyltriethoxysilane was after the addition of silica (b1). The results are shown in Table 1.
- Example 3 Except for changing the silica species from silica (b1) to silica (b2) (trade name “Nipsil E-74P”, manufactured by Tosoh Silica Co., Ltd., BET specific surface area: 45 m 2 / g), the same as Example 1
- a nitrile rubber composition and a rubber cross-linked product were prepared and evaluated in the same manner as in Example 1. The results are shown in Table 1.
- Example 4 Except for changing the silica species from silica (b1) to silica (b2) (trade name “Nipsil E-74P” manufactured by Tosoh Silica Co., Ltd., BET specific surface area: 45 m 2 / g), the same as Example 2 A nitrile rubber composition and a rubber cross-linked product were prepared and evaluated in the same manner as in Example 1. The results are shown in Table 1.
- Example 5 Instead of 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a1) obtained in Production Example 1, 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a2) obtained in Production Example 2 was used, and silica (b1 ) Is changed from 50 parts to 55 parts, and hexamethylenediamine carbamate is changed from 2.4 parts to 2.7 parts in the same manner as in Example 2, except that the nitrile rubber composition and rubber cross-linking are changed. A product was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 1.
- Example 6 Instead of 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a1) obtained in Production Example 1, 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a3) obtained in Production Example 3 was used, and silica (b1 ) Was changed from 50 parts to 60 parts, and instead of 5 parts of trimellitic acid tri-2-ethylhexyl, polyether ester (trade name “Adekaizer RS-700”, plasticizer, manufactured by ADEKA) 5 A nitrile rubber composition and a crosslinked rubber were prepared in the same manner as in Example 2 except that the amount of hexamethylenediamine carbamate was changed from 2.4 parts to 1.9 parts. Evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.
- Example 7 Except for changing the silica species from silica (b1) to silica (b3) (manufactured by PPG Industries, trade name “Hi-Sil 532EP”, BET specific surface area: 55 m 2 / g), the same as in Example 1.
- a nitrile rubber composition and a rubber cross-linked product were prepared and evaluated in the same manner as in Example 1. The results are shown in Table 1.
- Example 8 A nitrile rubber composition and a crosslinked rubber were prepared in the same manner as in Example 7 except that 1 part of 3-aminopropyltriethoxysilane was added, and evaluation was performed in the same manner as in Example 1. The addition timing of 3-aminopropyltriethoxysilane was the same as the addition of silica (b3). The results are shown in Table 1.
- Example 9 Instead of 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a1) obtained in Production Example 1, 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a2) obtained in Production Example 2 was used, and silica (b3 ) Was changed from 50 parts to 55 parts, and the amount of hexamethylenediamine carbamate was changed from 2.4 parts to 2.7 parts in the same manner as in Example 7, and the nitrile rubber composition and A rubber cross-linked product was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 1.
- Example 10 A nitrile rubber composition in the same manner as in Example 9 except that 5 parts of polyetherester was used in place of 5 parts of tri-2-ethylhexyl trimellitic acid and 1 part of 3-aminopropyltriethoxysilane was blended. A rubber cross-linked product was prepared and evaluated in the same manner as in Example 1. The addition timing of 3-aminopropyltriethoxysilane was the same as the addition of silica (b3). The results are shown in Table 1.
- Example 11 Instead of 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a1) obtained in Production Example 1, 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a3) obtained in Production Example 3 was used, and silica (b3 ) Was changed from 50 parts to 60 parts, 5 parts of polyetherester was used instead of 5 parts of tri-2-ethylhexyl trimellitic acid, and the amount of hexamethylenediamine carbamate was changed from 2.4 parts.
- a nitrile rubber composition and a rubber cross-linked product were produced in the same manner as in Example 7 except that the amount was changed to 1.9 parts, and evaluated in the same manner as in Example 1. The results are shown in Table 1.
- Example 12 A nitrile rubber composition in the same manner as in Example 11 except that 5 parts of trimellitic acid tri-2-ethylhexyl was used in place of 5 parts of the polyether ester and 1 part of 3-aminopropyltriethoxysilane was blended. A rubber cross-linked product was prepared and evaluated in the same manner as in Example 1. The addition timing of 3-aminopropyltriethoxysilane was the same as the addition of silica (b3). The results are shown in Table 1.
- Example 13 instead of 1 part of 3-aminopropyltriethoxysilane, 1 part of 3-glycidoxypropyltrimethoxysilane (manufactured by (Toray Dow Corning), trade name “(Z-6040 SILANE)”, silane coupling agent)
- a nitrile rubber composition and a rubber cross-linked product were prepared in the same manner as in Example 12 except that was used, and evaluated in the same manner as in Example 1. The results are shown in Table 1.
- Comparative Example 1 The silica species was changed from silica (b1) to silica (b'4) (trade name “Nipsil ER”, BET specific surface area: 111 m 2 / g, manufactured by Tosoh Silica Co., Ltd.), and changed to tri-2-ethylhexyl trimellitic acid Instead, a nitrile rubber composition and a rubber cross-linked product were produced in the same manner as in Example 1 except that a polyether ester (manufactured by ADEKA, trade name “ADEKA SIZER RS-700”, plasticizer) was used. Evaluation was performed in the same manner as in Example 1. The results are shown in Table 2.
- silica (b1) silica (b′5) (trade name “Carplex CS-7”, BET specific surface area: 109 m 2 / g) is used as the silica species, A nitrile rubber composition and a rubber cross-linked product were produced in the same manner as in Example 1 except that the amount was changed from 50 parts to 40 parts, and evaluated in the same manner as in Example 1. The results are shown in Table 2.
- Comparative Example 3 Except for using silica (b'6) (made by Nippon Aerosil Co., Ltd., trade name "AEROSIL (R) R972V", BET specific surface area: 110 m 2 / g) instead of silica (b'5) as the silica species.
- silica (b'6) made by Nippon Aerosil Co., Ltd., trade name "AEROSIL (R) R972V", BET specific surface area: 110 m 2 / g
- a nitrile rubber composition and a rubber cross-linked product were prepared in the same manner as in Comparative Example 2, and evaluated in the same manner as in Example 1. The results are shown in Table 2.
- Comparative Example 4 The silica type is changed from silica (b′5) to silica (b′7) (manufactured by Evonik, trade name “ULTRASIL VN2”, BET specific surface area: 130 m 2 / g), and the blending amount is 40 parts.
- a nitrile rubber composition and a rubber cross-linked product were produced in the same manner as in Comparative Example 2 except that the amount was changed from 50 parts to 50 parts, and evaluated in the same manner as in Example 1. The results are shown in Table 2.
- Comparative Example 5 Instead of 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a1) obtained in Production Example 1, 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a2) obtained in Production Example 2 was used, and silica (b In the same manner as in Comparative Example 4 except that the blending amount of '7) was changed from 50 parts to 55 parts and the blending amount of hexamethylenediamine carbamate was changed from 2.4 parts to 2.7 parts, A rubber cross-linked product was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 2.
- Comparative Example 6 A nitrile rubber composition and a rubber cross-linked product were prepared in the same manner as in Comparative Example 5 except that 1 part of 3-aminopropyltriethoxysilane was added, and evaluation was performed in the same manner as in Example 1. The addition timing of 3-aminopropyltriethoxysilane was the same as the addition of silica (b′7). The results are shown in Table 2.
- Comparative Example 7 In place of 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a1) obtained in Production Example 1, 100 parts of the carboxyl group-containing highly saturated nitrile rubber (a3) obtained in Production Example 3 was used, and silica (b In the same manner as in Comparative Example 4, except that the blending amount of '7) was changed from 50 parts to 60 parts and the blending amount of hexamethylenediamine carbamate was changed from 2.4 parts to 1.9 parts, A rubber cross-linked product was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 2.
- Comparative Example 8 A nitrile rubber composition and a rubber cross-linked product were prepared in the same manner as in Comparative Example 7 except that 1 part of 3-aminopropyltriethoxysilane was added, and evaluation was performed in the same manner as in Example 1. The addition timing of 3-aminopropyltriethoxysilane was the same as the addition of silica (b′7). The results are shown in Table 2.
- Comparative Example 9 A nitrile rubber composition and a rubber cross-linked product were prepared in the same manner as in Comparative Example 7 except that 1 part of 3-glycidoxypropyltrimethoxysilane was added, and evaluation was performed in the same manner as in Example 1. The addition timing of 3-glycidoxypropyltrimethoxysilane was the same as the addition of silica (b′7). The results are shown in Table 2.
- Tri-2-ethylhexyl trimellitic acid made by ADEKA, trade name “ADEKA SIZER C-8”, plasticizer
- 5 parts vinyl tris (2-methoxyethoxy) silane (Momentive Performance Materials) -Japan Co., Ltd., trade name "A-172”, silane coupling agent (1 part), trimethacrylic acid trimethylolpropane (Mitsubishi Rayon Co., trade name "Acryester TMP", vulcanization aid) 4 parts, 4 parts , 4'-di- ( ⁇ , ⁇ -dimethylbenzyl) diphenylamine (trade name “NOCRACK CD”, anti-aging agent, manufactured by Ouchi Shinsei Chemical Co., Ltd.) 1.5 parts, Mercaptobenzimidazole zinc salt (Ouchi Shinko Chemical Industrial Co., Ltd., antioxidant, Nocrac MBZ) 1 part, 1 part of stearic acid, by blending 2 parts of diethylene glycol, and mixed
- Comparative Example 11 The silica type is changed from silica (b1) to silica (b′4) (trade name “Nipsil ER”, BET specific surface area: 111 m 2 / g, manufactured by Tosoh Silica Co., Ltd.), and the blending amount is 50 to 40 parts.
- a nitrile rubber composition and a rubber cross-linked product were produced in the same manner as in Comparative Example 10 except that the change was made to Example 1 and evaluated in the same manner as in Example 1. The results are shown in Table 2.
- Comparative Example 12 A nitrile rubber composition and a rubber cross-linked product were obtained in the same manner as in Comparative Example 10 except that the silica species was changed from silica (b1) to silica (b′7) and the blending amount was changed from 50 parts to 40 parts. This was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 2.
- a carboxyl group-containing highly saturated nitrile rubber (a) containing 5 to 60% by weight of an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit and having an iodine value of 120 or less, and a specific surface area
- the rubber cross-linked product obtained by using the nitrile rubber composition containing silica (b) having a weight of 70 m 2 / g or less and the polyamine-based cross-linking agent (c) according to the present invention has a tensile strength and a breaking strength.
- Example 1-13 a carboxyl group-containing highly saturated nitrile rubber (a), by the specific surface area of a combination of silica and (b) is less than 70m 2 / g, a specific surface area of 70m 2 / g greater As compared with the case of using silica (b) (Comparative Examples 1 to 9, 11, 12) and the case of using nitrile rubber substantially not containing a carboxyl group (Comparative Examples 10 to 12), internal heat generation As a result, the dynamic exothermicity was extremely excellent.
- Examples 2, 4 to 6, 8, 10, 12, and 13 by using the silane coupling agent (d) in addition to silica (b) having a specific surface area of 70 m 2 / g or less, The tensile strength could be further improved while reducing internal heat generation. From this, it can be said that the rubber cross-linked product obtained by using the nitrile rubber composition of the present invention is particularly suitable for rubber parts used for vibrating parts.
- Example 1 the specific surface area is 48 m 2 / g.
- silica with a specific surface area of 111 m 2 / g was blended.
- silica with a specific surface area of 130 m 2 / g was blended.
- Comparative Example 10 and Comparative Examples 11 and 12 both use nitrile rubber (highly saturated nitrile rubber (a′4)) that does not substantially contain a carboxyl group. in, which specific surface area by blending silica 48m 2 / g, Comparative example 11, which specific surface area by blending silica 111m 2 / g, Comparative example 12, a specific surface area of 130m 2 / g of silica is blended.
- nitrile rubber highly saturated nitrile rubber (a′4)
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
Description
本発明のニトリルゴム組成物は、前記シリカ(b)の比表面積が、60m2/g以下であることが好ましい。
本発明のニトリルゴム組成物は、前記カルボキシル基含有高飽和ニトリルゴム(a)が、α,β-エチレン性不飽和ニトリル単量体単位5~60重量%、α,β-エチレン性不飽和ジカルボン酸モノエステル単量体単位0.1~30重量%、および共役ジエン単量体単位10~80重量%を含有することが好ましい。
本発明のニトリルゴム組成物は、塩基性架橋促進剤をさらに含有することが好ましい。
本発明のニトリルゴム組成物は、シランカップリング剤(d)をさらに含有することが好ましい。
本発明のニトリルゴム組成物は、可塑剤をさらに含有することが好ましい。
本発明のニトリルゴム組成物は、前記可塑剤が、トリメリット酸系可塑剤、エーテルエステル系可塑剤、およびアジピン酸エステル系可塑剤から選択される少なくとも一種であることが好ましい。
本発明で用いるα,β-エチレン性不飽和ニトリル単量体単位を5~60重量%の割合で含有し、ヨウ素価が120以下であるカルボキシル基含有高飽和ニトリルゴム(a)(以下、単に「カルボキシル基含有高飽和ニトリルゴム(a)」ということがある。)は、α,β-エチレン性不飽和ニトリル単量体、カルボキシル基含有単量体および必要に応じて加えられる共重合可能なその他の単量体を共重合することにより得られる、ヨウ素価が120以下のゴムである。
また、本発明のニトリルゴム組成物は、上述したカルボキシル基含有高飽和ニトリルゴム(a)に加えて、比表面積が70m2/g以下のシリカ(b)(以下、適宜、単に「シリカ(b)」という。)を含有してなる。本発明においては、上述したカルボキシル基含有高飽和ニトリルゴム(a)と、比表面積が70m2/g以下のシリカ(b)とを組み合わせて用いることで、該ゴムを架橋し、ゴム架橋物とした場合に、常態物性を良好なものとしながら、動的発熱を低く抑えることができるものである。なお、上述したシリカ(b)の比表面積は、各粒子の比表面積の平均値を示すものであり、そのため、シリカ(b)のうち一部の粒子の比表面積が70m2/gを超えていたとしても、シリカ(b)を構成する各粒子の比表面積の平均値が70m2/g以下であればよい。
なお、シリカ(b)の比表面積は、たとえば、ASTM D3037-81に準拠して、BET法にて測定することができる。
また、シリカ(b)の具体例としては、商品名「ニプシルEL」(東ソーシリカ社製、BET比表面積:48m2/g)、商品名「ニプシルE-74P」(東ソーシリカ社製、BET比表面積:45m2/g)、商品名「Hi-Sil 532EP」(PPG Industries社製、BET比表面積:55m2/g)などが挙げられる。
本発明のニトリルゴム組成物は、上述したカルボキシル基含有高飽和ニトリルゴム(a)、およびシリカ(b)に加えて、ポリアミン系架橋剤(c)を含有する。架橋剤として、ポリアミン系架橋剤(c)を用いることにより、得られるゴム架橋物の耐圧縮永久歪み性を適切に向上させることができる。
本発明のニトリルゴム組成物は、上述したカルボキシル基含有高飽和ニトリルゴム(a)、シリカ(b)、およびポリアミン系架橋剤(c)に加えて、シランカップリング剤(d)を含有していることが好ましい。シランカップリング剤(d)を配合することにより、ゴム架橋物とした場合に、得られるゴム架橋物の引張強さをより向上させることができる。
また、本発明のニトリルゴム組成物は、上述したカルボキシル基含有高飽和ニトリルゴム(a)、シリカ(b)、ポリアミン系架橋剤(c)、および必要に応じて配合されるシランカップリング剤(d)に加えて、本発明の作用効果をより顕著なものとすることができるという点より、塩基性架橋促進剤をさらに含有していることが好ましい。
また、R1およびR2は、置換基を有していないことが好ましい。
また、R3およびR4は、置換基を有していないことが好ましい。
グアニジン系塩基性架橋促進剤としては、テトラメチルグアニジン、テトラエチルグアニジン、ジフェニルグアニジン、1,3-ジ-オルト-トリルグアニジン、オルトトリルビグアニドなどが挙げられる。
アルデヒドアミン系塩基性架橋促進剤としては、n-ブチルアルデヒドアニリン、アセトアルデヒドアンモニアなどが挙げられる。
本発明のゴム架橋物は、上述した本発明のニトリルゴム組成物を架橋してなるものである。
本発明のゴム架橋物は、本発明のニトリルゴム組成物を用い、所望の形状に対応した成形機、たとえば、押出機、射出成形機、圧縮機、ロールなどにより成形を行い、加熱することにより架橋反応を行い、架橋物として形状を固定化することにより製造することができる。この場合においては、予め成形した後に架橋しても、成形と同時に架橋を行ってもよい。成形温度は、通常、10~200℃、好ましくは25~120℃である。架橋温度は、通常、100~200℃、好ましくは130~190℃であり、架橋時間は、通常、1分~24時間、好ましくは2分~1時間である。
加熱方法としては、プレス加熱、スチーム加熱、オーブン加熱、熱風加熱などのゴムの架橋に用いられる一般的な方法を適宜選択すればよい。
このため、本発明のゴム架橋物は、このような特性を活かし、O-リング、パッキン、ダイアフラム、ダンパ、オイルシール、シャフトシール、ベアリングシール、ウェルヘッドシール、ショックアブソーバシール、空気圧機器用シール、エアコンディショナの冷却装置や空調装置の冷凍機用コンプレッサに使用されるフロン若しくはフルオロ炭化水素または二酸化炭素の密封用シール、精密洗浄の洗浄媒体に使用される超臨界二酸化炭素または亜臨界二酸化炭素の密封用シール、転動装置(転がり軸受、自動車用ハブユニット、自動車用ウォーターポンプ、リニアガイド装置およびボールねじ等)用のシール、バルブおよびバルブシート、BOP(Blow Out Preventer)、プラターなどの各種シール材;インテークマニホールドとシリンダヘッドとの連接部に装着されるインテークマニホールドガスケット、シリンダブロックとシリンダヘッドとの連接部に装着されるシリンダヘッドガスケット、ロッカーカバーとシリンダヘッドとの連接部に装着されるロッカーカバーガスケット、オイルパンとシリンダブロックあるいはトランスミッションケースとの連接部に装着されるオイルパンガスケット、正極、電解質板および負極を備えた単位セルを挟み込む一対のハウジング間に装着される燃料電池セパレーター用ガスケット、ハードディスクドライブのトップカバー用ガスケットなどの各種ガスケット;印刷用ロール、製鉄用ロール、製紙用ロール、工業用ロール、事務機用ロールなどの各種ロール;平ベルト(フィルムコア平ベルト、コード平ベルト、積層式平ベルト、単体式平ベルト等)、Vベルト(ラップドVベルト、ローエッジVベルト等)、Vリブドベルト(シングルVリブドベルト、ダブルVリブドベルト、ラップドVリブドベルト、背面ゴムVリブドベルト、上コグVリブドベルト等)、CVT用ベルト、タイミングベルト、歯付ベルト、コンベアーベルト、などの各種ベルト;燃料ホース、ターボエアーホース、オイルホース、ラジェターホース、ヒーターホース、ウォーターホース、バキュームブレーキホース、コントロールホース、エアコンホース、ブレーキホース、パワーステアリングホース、エアーホース、マリンホース、ライザー、フローラインなどの各種ホース;CVJブーツ、プロペラシャフトブーツ、等速ジョイントブーツ、ラックアンドピニオンブーツなどの各種ブーツ;クッション材、ダイナミックダンパ、ゴムカップリング、空気バネ、防振材、クラッチフェーシング材などの減衰材ゴム部品;ダストカバー、自動車内装部材、摩擦材、タイヤ、被覆ケーブル、靴底、電磁波シールド、フレキシブルプリント基板用接着剤等の接着剤、燃料電池セパレーターの他、エレクトロニクス分野など幅広い用途に使用することができる。とりわけ、本発明のゴム架橋物は、動的発熱が低く抑えられたものであることから、振動する部分に使用されるシール材、たとえば、ダンパなどに好適に用いることができる。
2mm角のカルボキシル基含有高飽和ニトリルゴム0.2gに、2-ブタノン100mLを加えて16時間攪拌した後、エタノール20mLおよび水10mLを加え、攪拌しながら水酸化カリウムの0.02N含水エタノール溶液を用いて、室温でチモールフタレインを指示薬とする滴定により、ゴム100gに対するカルボキシル基のモル数として求めた(単位はephr)。
カルボキシル基含有高飽和ニトリルゴムを構成する各単量体単位の含有割合は、以下の方法により測定した。
すなわち、マレイン酸モノn-ブチル単位の含有割合は、上記「カルボキシル基含有量」の測定方法により、水素化後のカルボキシル基含有高飽和ニトリルゴム100gに対するカルボキシル基のモル数を求め、求めたモル数をマレイン酸モノn-ブチル単位の量に換算することにより算出した。
1,3-ブタジエン単位(水素化された部分も含む)の含有割合は、水素添加反応前のカルボキシル基含有ニトリルゴムのヨウ素価を下記方法で測定することにより算出した。
アクリロニトリル単位の含有割合は、JIS K6384に従い、ケルダール法により、水素化後のカルボキシル含有高飽和ニトリルゴム中の窒素含量を測定することにより算出した。
アクリル酸メトキシエチル単位の含有割合は、上記各単量体単位の残部として算出した。
カルボキシル基含有高飽和ニトリルゴムのヨウ素価は、JIS K 6235に準じて測定した。
カルボキシル基高飽和含有ニトリルゴムのムーニー粘度(ポリマームーニー)は、JIS K6300に従って測定した(単位は〔ML1+4、100℃〕)。
ニトリルゴム組成物を、縦15cm、横15cm、深さ0.2cmの金型に入れ、プレス圧10MPaで加圧しながら170℃で20分間プレス成形してシート状の一次架橋物を得た。次いで、得られた一次架橋物をギヤー式オーブンに移して170℃で4時間二次架橋し、得られたシート状のゴム架橋物を3号形ダンベルで打ち抜いて試験片を作製した。そして、得られたこの試験片を用いて、JIS K6251に従い、ゴム架橋物の引張強さおよび破断伸びを、また、JIS K6253に従い、デュロメータ硬さ試験機(タイプA)を用いてゴム架橋物の硬さを、それぞれ測定した。
発熱性は、ASTM D 623-78で規定されるフレクソメータ試験で評価した。具体的には、まず、直径17.8±0.15mm、深さ25±0.25mmの円柱状金型に入れ、170℃で20分間、架橋した後、170℃で4時間二次架橋を行うことにより、フレクソメータ試験用試験片を得た。そして、フレクソメータ(GABOメーター4000、GABO社製)を用いて、試験温度100℃、初期荷重1MPa、動的変位4.45mmの条件で25分間動的変位を加えることで、発熱試験を行った。なお、この際において測定周波数は30Hzとした。そして、発熱試験の結果から、HBU 内部(内部発熱量:測定された試験片内部の温度と雰囲気温度100℃との差を発熱温度とした。)を測定した。HBU 内部は小さいほど動的発熱が小さく、動的発熱性に優れている。
反応器に、イオン交換水220部、濃度10%のドデシルベンゼンスルホン酸ナトリウム水溶液5部、アクリロニトリル37部、マレイン酸モノn-ブチル4部、およびt-ドデシルメルカプタン(分子量調整剤)0.75部の順に仕込み、内部の気体を窒素で3回置換した後、1,3-ブタジエン57部を仕込んだ。そして、反応器を10℃に保ち、クメンハイドロパーオキサイド(重合開始剤)0.06部、還元剤、およびキレート剤適量を仕込み、攪拌しながら重合反応を継続し、重合転化率が40%、および60%になった時点で、それぞれ1部のマレイン酸モノn-ブチルを添加し、重合転化率が85%になった時点で、濃度10重量%のハイドロキノン水溶液(重合停止剤)0.1部を加えて重合反応を停止した。次いで、水温60℃で残留単量体を除去し、ニトリルゴムのラテックス(固形分濃度30重量%)を得た。
反応器に、イオン交換水180部、濃度10%のドデシルベンゼンスルホン酸ナトリウム水溶液25部、アクリロニトリル23部、マレイン酸モノn-ブチル6.5部、アクリル酸メトキシエチル30.5部、およびt-ドデシルメルカプタン(分子量調整剤)0.65部の順に仕込み、内部の気体を窒素で3回置換した後、1,3-ブタジエン40部を仕込んだ。そして、反応器を10℃に保ち、クメンハイドロパーオキサイド(重合開始剤)0.06部、還元剤、およびキレート剤適量を仕込み、攪拌しながら重合反応を継続し、重合転化率が83%になった時点で、濃度10重量%のハイドロキノン水溶液(重合停止剤)0.1部を加えて重合反応を停止した。次いで、水温60℃で残留単量体を除去し、ニトリルゴムのラテックス(固形分濃度30重量%)を得た。
反応器に、イオン交換水180部、濃度10重量%のドデシルベンゼンスルホン酸ナトリウム水溶液25部、アクリロニトリル20.4部、マレイン酸モノn-ブチル5部、アクリル酸n-ブチル35.2部、t-ドデシルメルカプタン(第2アルキルチオール化合物)0.35部、および2,2,4,6,6-ペンタメチル-4-ヘプタンチオール(第1アルキルチオール化合物)0.03部を、この順に仕込み、内部の気体を窒素で3回置換した後、1,3-ブタジエン39.4部を仕込んだ。次いで、反応器内を10℃に保ち、クメンハイドロパーオキサイド(重合開始剤)0.1部、還元剤、およびキレート剤適量を仕込み、攪拌しながら重合反応を継続した。そして、重合転化率が90%になった時点で、濃度10重量%のハイドロキノン水溶液(重合停止剤)0.1部を加えて重合反応を停止した。次いで、水温60℃のロータリーエバポレータを用いて残留単量体を除去し、ニトリルゴムのラテックス(固形分濃度約30重量%)を得た。
反応器内でイオン交換水200部に、炭酸ナトリウム0.2部を溶解し、それに脂肪酸カリウム石鹸(脂肪酸のカリウム塩)2.25部を添加して石鹸水溶液を調製した。そして、この石鹸水溶液に、アクリロニトリル37部、およびt-ドデシルメルカプタン(分子量調整剤)0.47部をこの順に仕込み、内部の気体を窒素で3回置換した後、1,3-ブタジエン63部を仕込んだ。次いで、反応器内を5℃に保ち、クメンハイドロパーオキサイド(重合開始剤)0.1部、還元剤、およびキレート剤適量を仕込み、温度を5℃に保ちながら16時間重合反応を行なった。次いで、濃度10%のハイドロキノン(重合停止剤)水溶液0.1部を加えて重合反応を停止し、水温60℃のロータリーエバポレ-タを用いて残留単量体を除去して、ニトリルゴムのラテックス(固形分濃度約25重量%
)を得た。
バンバリーミキサを用いて、製造例1で得られたカルボキシル基含有高飽和ニトリルゴム(a1)100部に、シリカ(b1)(東ソー・シリカ社製、商品名「ニプシルEL」、BET比表面積:48m2/g)50部、トリメリット酸トリ-2-エチルヘキシル(ADEKA社製、商品名「アデカサイザーC-8」、可塑剤)5部、4,4’-ジ-(α,α-ジメチルベンジル)ジフェニルアミン(大内新興化学社製、商品名「ノクラックCD」、老化防止剤)1.5部、ステアリン酸1部、ポリオキシエチレンアルキルエーテルリン酸エステル(東邦化学工業社製、商品名「フォスファノールRL210」、加工助剤)1部を配合して、50℃で5分間混合した。次いで、得られた混合物を50℃のロールに移して、1,8-ジアザビシクロ[5,4,0]-ウンデセン-7(DBU)(RheinChemie社製、商品名「RHENOGRAN XLA-60(GE2014)」、DBU60%(ジンクジアルキルジフォスフェイト塩になっている部分も含む)、塩基性架橋促進剤)4部、ヘキサメチレンジアミンカルバメート(デュポンダウエラストマー社製、商品名「Diak#1」、脂肪族多価アミン類に属するポリアミン架橋剤)2.4部を配合して、混練することにより、ニトリルゴム組成物を得た。
3-アミノプロピルトリエトキシシラン(東レ・ダウコーニング社製、商品名「Z-6011 SILANE」、シランカップリング剤)を1部配合した以外は、実施例1と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。なお、3-アミノプロピルトリエトキシシランの添加タイミングは、シリカ(b1)の添加後とした。結果を表1に示す。
シリカ種を、シリカ(b1)からシリカ(b2)(東ソー・シリカ社製、商品名「ニプシルE-74P」、BET比表面積:45m2/g)に変更した以外は、実施例1と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表1に示す。
シリカ種を、シリカ(b1)からシリカ(b2)(東ソー・シリカ社製、商品名「ニプシルE-74P」、BET比表面積:45m2/g)に変更した以外は、実施例2と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表1に示す。
製造例1で得られたカルボキシル基含有高飽和ニトリルゴム(a1)100部に代えて、製造例2で得られたカルボキシル基含有高飽和ニトリルゴム(a2)100部を使用するとともに、シリカ(b1)の配合量を50部から55部へ、ヘキサメチレンジアミンカルバメートの配合量を2.4部から2.7部へ変更した以外は、実施例2と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表1に示す。
製造例1で得られたカルボキシル基含有高飽和ニトリルゴム(a1)100部に代えて、製造例3で得られたカルボキシル基含有高飽和ニトリルゴム(a3)100部を使用するとともに、シリカ(b1)の配合量を50部から60部へ変更し、トリメリット酸トリ-2-エチルヘキシル5部に代えて、ポリエーテルエステル(ADEKA社製、商品名「アデカサイザーRS-700」、可塑剤)5部を使用し、ヘキサメチレンジアミンカルバメートの配合量を2.4部から1.9部へ変更した以外は、実施例2と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表1に示す。
シリカ種を、シリカ(b1)からシリカ(b3)(PPG Industries社製、商品名「Hi-Sil 532EP」、BET比表面積:55m2/g)に変更した以外は、実施例1と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表1に示す。
3-アミノプロピルトリエトキシシランを1部配合した以外は、実施例7と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。なお、3-アミノプロピルトリエトキシシランの添加タイミングは、シリカ(b3)の添加と同時とした。結果を表1に示す。
製造例1で得られたカルボキシル基含有高飽和ニトリルゴム(a1)100部に代えて、製造例2で得られたカルボキシル基含有高飽和ニトリルゴム(a2)100部を使用するとともに、シリカ(b3)の配合量を50部から55部へ変更し、ヘキサメチレンジアミンカルバメートの配合量を2.4部から2.7部へ変更した以外は、実施例7と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表1に示す。
トリメリット酸トリ-2-エチルヘキシル5部に代えて、ポリエーテルエステル5部を使用し、3-アミノプロピルトリエトキシシランを1部配合した以外は、実施例9と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。なお、3-アミノプロピルトリエトキシシランの添加タイミングは、シリカ(b3)の添加と同時とした。結果を表1に示す。
製造例1で得られたカルボキシル基含有高飽和ニトリルゴム(a1)100部に代えて、製造例3で得られたカルボキシル基含有高飽和ニトリルゴム(a3)100部を使用するとともに、シリカ(b3)の配合量を50部から60部へ変更し、トリメリット酸トリ-2-エチルヘキシル5部に代えて、ポリエーテルエステル5部を使用し、ヘキサメチレンジアミンカルバメートの配合量を2.4部から1.9部へ変更した以外は、実施例7と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表1に示す。
ポリエーテルエステル5部に代えて、トリメリット酸トリ-2-エチルヘキシル5部を使用し、3-アミノプロピルトリエトキシシランを1部配合した以外は、実施例11と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。なお、3-アミノプロピルトリエトキシシランの添加タイミングは、シリカ(b3)の添加と同時とした。結果を表1に示す。
3-アミノプロピルトリエトキシシラン1部に代えて、3-グリシドキシプロピルトリメトキシシラン((東レ・ダウコーニング)社製、商品名「(Z-6040 SILANE)」、シランカップリング剤)1部を使用した以外は、実施例12と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表1に示す。
シリカ種をシリカ(b1)からシリカ(b’4)(東ソー・シリカ社製、商品名「ニプシルER」、BET比表面積:111m2/g)に変更し、トリメリット酸トリ-2-エチルヘキシルに代えて、ポリエーテルエステル(ADEKA社製、商品名「アデカサイザーRS-700」、可塑剤)を使用した以外は、実施例1と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表2に示す。
シリカ種として、シリカ(b1)に代えて、シリカ(b’5)(エボニック社製、商品名「カープレックスCS-7」、BET比表面積:109m2/g)を使用するとともに、配合量を50部から40部へ変更した以外は、実施例1と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表2に示す。
シリカ種として、シリカ(b’5)に代えて、シリカ(b’6)(日本アエロジル社製、商品名「AEROSIL(R) R972V」、BET比表面積:110m2/g)を使用した以外は、比較例2と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表2に示す。
シリカ種として、シリカ(b’5)から、シリカ(b’7)(Evonik社製、商品名「ULTRASIL VN2」、BET比表面積:130m2/g)に変更するとともに、その配合量を40部から50部へ変更した以外は、比較例2と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表2に示す。
製造例1で得られたカルボキシル基含有高飽和ニトリルゴム(a1)100部に代えて、製造例2で得られたカルボキシル基含有高飽和ニトリルゴム(a2)100部を使用するとともに、シリカ(b’7)の配合量を50部から55部へ、ヘキサメチレンジアミンカルバメートの配合量を2.4部から2.7部へ変更した以外は、比較例4と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表2に示す。
3-アミノプロピルトリエトキシシランを1部配合した以外は、比較例5と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。なお、3-アミノプロピルトリエトキシシランの添加タイミングは、シリカ(b’7)の添加と同時とした。結果を表2に示す。
製造例1で得られたカルボキシル基含有高飽和ニトリルゴム(a1)100部に代えて、製造例3で得られたカルボキシル基含有高飽和ニトリルゴム(a3)100部を使用するとともに、シリカ(b’7)の配合量を50部から60部へ、ヘキサメチレンジアミンカルバメートの配合量を2.4部から1.9部へ変更した以外は、比較例4と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表2に示す。
3-アミノプロピルトリエトキシシランを1部配合した以外は、比較例7と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。なお、3-アミノプロピルトリエトキシシランの添加タイミングは、シリカ(b’7)の添加と同時とした。結果を表2に示す。
3-グリシドキシプロピルトリメトキシシランを1部配合した以外は、比較例7と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。なお、3-グリシドキシプロピルトリメトキシシランの添加タイミングは、シリカ(b’7)の添加と同時とした。結果を表2に示す。
バンバリーミキサを用いて、製造例4で得られた高飽和ニトリルゴム(a’4)100部に、シリカ(b1)(東ソー・シリカ社製、商品名「ニプシルEL」、BET比表面積:48m2/g)50部、トリメリット酸トリ-2-エチルヘキシル(ADEKA社製、商品名「アデカサイザーC-8」、可塑剤)5部、ビニルトリス(2-メトキシエトキシ)シラン(モメンティブ・パフォーマンス・マテリアルズ・ジャパン社製、商品名「A-172」、シランカップリング剤)1部、トリメタクリル酸トリメチロールプロパン(三菱レイヨン社製、商品名「アクリエステルTMP」、加硫助剤)4部、4,4’-ジ-(α,α-ジメチルベンジル)ジフェニルアミン(大内新興化学社製、商品名「ノクラックCD」、老化防止剤)1.5部、2-メルカプトベンゾイミダゾール亜鉛塩(大内新興化学工業社製、老化防止剤、ノクラック MBZ)1部、ステアリン酸1部、ジエチレングリコール2部を配合して、50℃で5分間混合した。次いで、得られた混合物を50℃のロールに移して、1,3-ビス(t-ブチルパーオキシイソプロピル)ベンゼン(有機過酸化物)40%品(ハーキュレス社製、バルカップ40KE)8部を配合して、混練することにより、ニトリルゴム組成物を得た。
シリカ種をシリカ(b1)からシリカ(b’4)(東ソー・シリカ社製、商品名「ニプシルER」、BET比表面積:111m2/g)に変更するとともに、配合量を50部から40部へ変更した以外は、比較例10と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表2に示す。
シリカ種をシリカ(b1)からシリカ(b’7)に変更するとともに、配合量を50部から40部へ変更した以外は、比較例10と同様にして、ニトリルゴム組成物およびゴム架橋物を作製し、実施例1と同様にして評価を行った。結果を表2に示す。
また、ニトリルゴムとして、カルボキシル基を実質的に含有しないものを用いた場合には、得られるゴム架橋物は、内部発熱が大きく、動的発熱性が悪くなる(動的発熱が大きい)という結果となった(比較例10~12)。特に、ニトリルゴムとして、カルボキシル基を実質的に含有しないものを用い、かつ、比表面積が70m2/g超であるシリカ(b)を用いた場合には、内部発熱が最も大きくなるという結果となった(比較例11,12)。
以上のように、本発明によれば、常態物性を良好にしながら、動的発熱の小さいゴム架橋物を得ることできるものであり、たとえば、このような本発明の効果は、実施例1および比較例1,4と、比較例10および比較例11,12とを比較することから明らかである。
すなわち、実施例1と、比較例1,4とは、共に、本発明所定のカルボキシル基含有高飽和ニトリルゴム(a)を用いるものであり、実施例1では、比表面積が48m2/gのシリカを配合したものであり、比較例1では、比表面積が111m2/gのシリカを配合したものであり、比較例4では、比表面積が130m2/gのシリカを配合したものである。そして、このような比較例1と、実施例1とを比較すると、比表面積が111m2/gのシリカに代えて、比表面積が48m2/gのシリカを用いることにより、内部発熱の低下量は、18となっている。また、比較例4と、実施例1とを比較すると、比表面積が130m2/gのシリカに代えて、比表面積が48m2/gのシリカを用いることにより、内部発熱の低下量は、37となっている。
その一方で、比較例10と、比較例11,12とは、いずれも、カルボキシル基を実質的に含有しないニトリルゴム(高飽和ニトリルゴム(a’4))を用いるものであり、比較例10では、比表面積が48m2/gのシリカを配合したものであり、比較例11では、比表面積が111m2/gのシリカを配合したものであり、比較例12では、比表面積が130m2/gのシリカを配合したものである。そして、このような比較例10と、比較例11とを比較すると、比表面積が111m2/gのシリカに代えて、比表面積が48m2/gのシリカを用いたにもかかわらず、内部発熱の低下量は9であった。同様に、比較例10と、実施例12とを比較すると、比表面積が130m2/gのシリカに代えて、比表面積が48m2/gのシリカを用いたにもかかわらず、内部発熱の低下量は9であった。
すなわち、カルボキシル基を含有しないニトリルゴムを用いた場合、内部発熱の低下量は9と小さいのに対して、カルボキシル基含有高飽和ニトリルゴム(a)を用いた場合には、内部発熱の低下量が18(実施例1と比較例1との比較)や37(実施例1と比較例4との比較)と大きくなるという結果であった。
以上により、本発明のように、カルボキシル基含有高飽和ニトリルゴム(a)と、比表面積が70m2/g以下であるシリカ(b)とを組み合わせて用いることで、これらの相乗効果によって、内部発熱を顕著に低下させることができることが確認できる。
Claims (10)
- α,β-エチレン性不飽和ニトリル単量体単位を5~60重量%の割合で含有し、ヨウ素価が120以下であるカルボキシル基含有高飽和ニトリルゴム(a)と、比表面積が70m2/g以下であるシリカ(b)と、ポリアミン系架橋剤(c)とを含有し、
前記カルボキシル基含有高飽和ニトリルゴム(a)100重量部に対する、前記ポリアミン系架橋剤(c)の含有量が0.1~20重量部であることを特徴とするニトリルゴム組成物。 - 前記シリカ(b)が、合成シリカである請求項1に記載のニトリルゴム組成物。
- 前記カルボキシル基含有高飽和ニトリルゴム(a)100重量部に対する、前記シリカ(b)の含有量が、10~100重量部である請求項1または2に記載のニトリルゴム組成物。
- 前記シリカ(b)の比表面積が、60m2/g以下である請求項1~3のいずれかに記載のニトリルゴム組成物。
- 前記カルボキシル基含有高飽和ニトリルゴム(a)が、α,β-エチレン性不飽和ニトリル単量体単位5~60重量%、α,β-エチレン性不飽和ジカルボン酸モノエステル単量体単位0.1~30重量%、および共役ジエン単量体単位10~80重量%を含有する請求項1~4のいずれかに記載のニトリルゴム組成物。
- 塩基性架橋促進剤をさらに含有する請求項1~5のいずれかに記載のニトリルゴム組成物。
- シランカップリング剤(d)をさらに含有する請求項1~6のいずれかに記載のニトリルゴム組成物。
- 可塑剤をさらに含有する請求項1~7のいずれかに記載のニトリルゴム組成物。
- 前記可塑剤が、トリメリット酸系可塑剤、エーテルエステル系可塑剤、およびアジピン酸エステル系可塑剤から選択される少なくとも一種である請求項8に記載のニトリルゴム組成物。
- 請求項1~9のいずれかに記載のニトリルゴム組成物を架橋してなるゴム架橋物。
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP16824350.9A EP3323850B1 (en) | 2015-07-15 | 2016-07-06 | Nitrile rubber composition and cross-linked rubber |
JP2017528623A JP6798492B2 (ja) | 2015-07-15 | 2016-07-06 | ニトリルゴム組成物およびゴム架橋物 |
KR1020187004396A KR20180030648A (ko) | 2015-07-15 | 2016-07-06 | 니트릴 고무 조성물 및 고무 가교물 |
US15/744,177 US20180194924A1 (en) | 2015-07-15 | 2016-07-06 | Nitrile rubber composition and cross-linked rubber |
CN201680040948.7A CN107849314A (zh) | 2015-07-15 | 2016-07-06 | 腈橡胶组合物和橡胶交联物 |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2015141140 | 2015-07-15 | ||
JP2015-141140 | 2015-07-15 | ||
JP2016-015788 | 2016-01-29 | ||
JP2016015788 | 2016-01-29 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2017010370A1 true WO2017010370A1 (ja) | 2017-01-19 |
Family
ID=57757906
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2016/069997 WO2017010370A1 (ja) | 2015-07-15 | 2016-07-06 | ニトリルゴム組成物およびゴム架橋物 |
Country Status (7)
Country | Link |
---|---|
US (1) | US20180194924A1 (ja) |
EP (1) | EP3323850B1 (ja) |
JP (1) | JP6798492B2 (ja) |
KR (1) | KR20180030648A (ja) |
CN (1) | CN107849314A (ja) |
TW (1) | TWI719997B (ja) |
WO (1) | WO2017010370A1 (ja) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2018163734A1 (ja) * | 2017-03-08 | 2018-09-13 | 日本ゼオン株式会社 | ラテックス組成物 |
JP2018150505A (ja) * | 2017-03-13 | 2018-09-27 | 横浜ゴム株式会社 | タイヤ用ゴム組成物および空気入りタイヤ |
WO2019020392A1 (en) | 2017-07-25 | 2019-01-31 | Arlanxeo Deutschland Gmbh | VULCANIZABLE COMPOSITIONS COMPRISING A CARBOXYLIC-DIENE-NITRILE HYDROGENATED ESTER COPOLYMER AND SILICA |
WO2019146526A1 (ja) * | 2018-01-26 | 2019-08-01 | 日本ゼオン株式会社 | カルボキシ基含有水素化ニトリルゴムの製造方法 |
JP2019206602A (ja) * | 2018-05-28 | 2019-12-05 | Nok株式会社 | 摺動シール部材用ポリアミン加硫性カルボキシル基含有水素化ニトリルゴム組成物 |
JP2022551795A (ja) * | 2019-08-09 | 2022-12-14 | シントマー スンディリアン ブルハド | 自己回復特性を有するエラストマーフィルムの調製のためのポリマーラテックス組成物 |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016148055A1 (ja) * | 2015-03-13 | 2016-09-22 | 日本ゼオン株式会社 | ニトリルゴム組成物およびゴム架橋物 |
MX2018002923A (es) * | 2015-09-17 | 2018-12-10 | Zeon Corp | Composicion de caucho de nitrilo, composicion de caucho de nitrilo retriculable, y caucho reticulado. |
EP3816221B1 (en) * | 2018-06-27 | 2023-02-15 | Zeon Corporation | Crosslinkable nitrile rubber composition and crosslinked rubber material |
JP2020128737A (ja) * | 2019-02-08 | 2020-08-27 | 株式会社マーレ フィルターシステムズ | エンジン吸気系用シール部品、及び、エンジン吸気系のシール構造 |
KR102536743B1 (ko) * | 2019-10-11 | 2023-05-26 | 주식회사 엘지화학 | 니트릴계 고무의 제조방법, 이로부터 제조된 니트릴계 고무 및 상기 고무를 포함하는 고무 조성물 |
KR102251967B1 (ko) * | 2019-10-25 | 2021-05-17 | 금호석유화학 주식회사 | 딥 성형용 라텍스 조성물, 그 제조방법 및 그로부터 제조된 딥 성형품 |
TW202239790A (zh) * | 2021-03-19 | 2022-10-16 | 馬來西亞商昕特瑪私人有限公司 | 聚合物乳膠組成物 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003120824A (ja) * | 2001-07-23 | 2003-04-23 | Nsk Ltd | シール |
WO2010038720A1 (ja) * | 2008-09-30 | 2010-04-08 | 日本ゼオン株式会社 | ニトリル基含有高飽和共重合ゴム、これを含有する架橋性ゴム組成物および架橋物 |
WO2013175878A1 (ja) * | 2012-05-24 | 2013-11-28 | Nok株式会社 | ポリアミン加硫性高飽和ニトリルゴム組成物 |
WO2013175877A1 (ja) * | 2012-05-24 | 2013-11-28 | Nok株式会社 | ポリアミン加硫性高飽和ニトリルゴム組成物 |
WO2014050853A1 (ja) * | 2012-09-26 | 2014-04-03 | 日本ゼオン株式会社 | 架橋性ゴム組成物およびゴム架橋物 |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10307137A1 (de) * | 2003-02-20 | 2004-09-02 | Bayer Ag | Zusammensetzung |
DE102004058063A1 (de) * | 2004-12-02 | 2006-06-08 | Lanxess Deutschland Gmbh | Mischungen aus Ethylen-Vinylalkohol-Copolymerisaten und vernetzbaren Kautschuken mit reaktiven Gruppierungen sowie deren Verwendung zur Herstellung von geformten Artikeln mit guten Barriere-Eigenschaften |
US8742006B2 (en) * | 2006-04-17 | 2014-06-03 | Zeon Corporation | Cross-linkable nitrile rubber composition and cross-linked rubber |
EP2145920A1 (en) * | 2008-07-15 | 2010-01-20 | Lanxess Deutschland GmbH | Vulcanizable polymer compositions |
EP2660285B1 (en) * | 2010-12-27 | 2016-05-25 | Zeon Corporation | Rubber composition and crosslinked rubber product |
US9163136B2 (en) * | 2011-11-18 | 2015-10-20 | Zeon Corporation | Nitrile rubber composition and cross-linked rubber |
EP2891694B1 (en) * | 2012-08-31 | 2018-06-06 | Zeon Corporation | Adhesive agent composition |
JPWO2014192844A1 (ja) * | 2013-05-30 | 2017-02-23 | 日本ゼオン株式会社 | ニトリル共重合体ゴム組成物、架橋性ゴム組成物およびゴム架橋物 |
-
2016
- 2016-07-06 EP EP16824350.9A patent/EP3323850B1/en active Active
- 2016-07-06 US US15/744,177 patent/US20180194924A1/en not_active Abandoned
- 2016-07-06 JP JP2017528623A patent/JP6798492B2/ja active Active
- 2016-07-06 CN CN201680040948.7A patent/CN107849314A/zh active Pending
- 2016-07-06 WO PCT/JP2016/069997 patent/WO2017010370A1/ja active Application Filing
- 2016-07-06 KR KR1020187004396A patent/KR20180030648A/ko not_active Application Discontinuation
- 2016-07-07 TW TW105121509A patent/TWI719997B/zh active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003120824A (ja) * | 2001-07-23 | 2003-04-23 | Nsk Ltd | シール |
WO2010038720A1 (ja) * | 2008-09-30 | 2010-04-08 | 日本ゼオン株式会社 | ニトリル基含有高飽和共重合ゴム、これを含有する架橋性ゴム組成物および架橋物 |
WO2013175878A1 (ja) * | 2012-05-24 | 2013-11-28 | Nok株式会社 | ポリアミン加硫性高飽和ニトリルゴム組成物 |
WO2013175877A1 (ja) * | 2012-05-24 | 2013-11-28 | Nok株式会社 | ポリアミン加硫性高飽和ニトリルゴム組成物 |
WO2014050853A1 (ja) * | 2012-09-26 | 2014-04-03 | 日本ゼオン株式会社 | 架橋性ゴム組成物およびゴム架橋物 |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2018163734A1 (ja) * | 2017-03-08 | 2018-09-13 | 日本ゼオン株式会社 | ラテックス組成物 |
JP7131540B2 (ja) | 2017-03-08 | 2022-09-06 | 日本ゼオン株式会社 | ラテックス組成物 |
JPWO2018163734A1 (ja) * | 2017-03-08 | 2020-01-09 | 日本ゼオン株式会社 | ラテックス組成物 |
JP7024306B2 (ja) | 2017-03-13 | 2022-02-24 | 横浜ゴム株式会社 | タイヤ用ゴム組成物および空気入りタイヤ |
JP2018150505A (ja) * | 2017-03-13 | 2018-09-27 | 横浜ゴム株式会社 | タイヤ用ゴム組成物および空気入りタイヤ |
WO2019020392A1 (en) | 2017-07-25 | 2019-01-31 | Arlanxeo Deutschland Gmbh | VULCANIZABLE COMPOSITIONS COMPRISING A CARBOXYLIC-DIENE-NITRILE HYDROGENATED ESTER COPOLYMER AND SILICA |
WO2019146526A1 (ja) * | 2018-01-26 | 2019-08-01 | 日本ゼオン株式会社 | カルボキシ基含有水素化ニトリルゴムの製造方法 |
JPWO2019146526A1 (ja) * | 2018-01-26 | 2021-01-07 | 日本ゼオン株式会社 | カルボキシ基含有水素化ニトリルゴムの製造方法 |
US11370849B2 (en) | 2018-01-26 | 2022-06-28 | Zeon Corporation | Method for producing carboxy group-containing hydrogenated nitrile rubber |
JP7173051B2 (ja) | 2018-01-26 | 2022-11-16 | 日本ゼオン株式会社 | カルボキシ基含有水素化ニトリルゴムの製造方法 |
JP2019206602A (ja) * | 2018-05-28 | 2019-12-05 | Nok株式会社 | 摺動シール部材用ポリアミン加硫性カルボキシル基含有水素化ニトリルゴム組成物 |
JP2022551795A (ja) * | 2019-08-09 | 2022-12-14 | シントマー スンディリアン ブルハド | 自己回復特性を有するエラストマーフィルムの調製のためのポリマーラテックス組成物 |
JP7407270B2 (ja) | 2019-08-09 | 2023-12-28 | シントマー スンディリアン ブルハド | 自己回復特性を有するエラストマーフィルムの調製のためのポリマーラテックス組成物 |
Also Published As
Publication number | Publication date |
---|---|
TW201710350A (zh) | 2017-03-16 |
US20180194924A1 (en) | 2018-07-12 |
EP3323850A1 (en) | 2018-05-23 |
CN107849314A (zh) | 2018-03-27 |
KR20180030648A (ko) | 2018-03-23 |
EP3323850A4 (en) | 2019-01-23 |
JPWO2017010370A1 (ja) | 2018-04-26 |
EP3323850B1 (en) | 2020-11-11 |
TWI719997B (zh) | 2021-03-01 |
JP6798492B2 (ja) | 2020-12-09 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6798492B2 (ja) | ニトリルゴム組成物およびゴム架橋物 | |
EP3305817B1 (en) | Nitrile group containing, highly saturated copolymer rubber | |
US10287382B2 (en) | Nitrile rubber composition and cross-linked rubber | |
US10787525B2 (en) | Rubber crosslinked material | |
JP6969384B2 (ja) | ニトリルゴム組成物、架橋性ニトリルゴム組成物およびゴム架橋物 | |
WO2016190214A1 (ja) | ニトリル基含有高飽和共重合体ゴム | |
US11286324B2 (en) | Carboxyl group-containing nitrile rubber, method for production same, crosslinkable nitrile rubber composition, and crosslinked rubber | |
WO2018168395A1 (ja) | ニトリル基含有共重合体ゴム | |
US11414499B2 (en) | Crosslinkable nitrile rubber composition and crosslinked rubber material | |
JP6733658B2 (ja) | ニトリルゴム組成物およびゴム架橋物 | |
WO2018198998A1 (ja) | ゴム架橋物の製造方法 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 16824350 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2017528623 Country of ref document: JP Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
ENP | Entry into the national phase |
Ref document number: 20187004396 Country of ref document: KR Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2016824350 Country of ref document: EP |